
Students under siege at a Hong Kong university are trying to escape through the sewers amid fears that police will storm the campus and open fire, causing a Tiananmen Square-style massacre.

Dozens of activists at Hong Kong Polytechnic University wrapped their knees and arms in plastic on Tuesday as they prepared to try and crawl to freedom through a perilous maze of underground tunnels.

There are thought to be between 100 and 200 students left on campus, locked into the third day of a violent standoff with police who are trying to get inside and break up the pro-democracy demonstration.

Around 600 people surrendered overnight Monday, 200 of whom were children who were questioned and released, alongside 400 adults who were arrested and now face 10 years in jail accused of rioting.

Speaking Tuesday morning, city chief executive Carrie Lam said the only option for the remaining demonstrators was to lay down their weapons, surrender and face the legal consequences.

While Hong Kong police chiefs refused to say Tuesday what their next steps will be, commanders have previously said they are willing to resort to using live ammunition if the situation becomes 'uncontrollable'.

That has led to fears of a repeat of the 1989 Tiananmen Square massacre, when peaceful pro-democracy student protesters were shot dead by the Chinese army.

Dozens of students trapped on the Hong Kong Polytechnic University campus by a ring of police launched a desperate and risky escape attempt on Tuesday by crawling through the sewers

Hong Kong leader Carrie Lam has urged the protesters to surrender on Tuesday, but faced with a possible 10-year jail sentence for rioting, many opted to try and escape instead

Students are also fearful of a Tiananmen Square-style massacre after police said they would be willing to use live ammunition if the situation spirals out of control

Fearful of bloodshed and being arrested by police, many protesters staged increasingly desperate attempts to escape the campus, including lowering themselves into the sewer system

An anti-government protester attempts to escape Hong Kong Polytechnic University by going through a sewer

Student activists gather around an open manhole at the PolyU campus as they explore the sewer tunnels in an attempt to find a way off campus that will avoid both bloodshed and arrest

A police officer brandishes a baton as a student, along with others who tried to evade capture at the PolyU campus, cower inside bushes close to a fence on Tuesday night

Police detain protesters and students at PolyU after they were discovered tying to hide inside a hedge at the campus in the Hung Hom district

Police escort a young man after he allegedly tried to escape from Hong Kong Polytechnic University on Tuesday night

Police officers arrest student protesters forced to lie on their fronts at the PolyU campus in Hong Kong on Tuesday night

Police officers wearing heavy riot gear escort young men from the scene on Tuesday night after they attempted to escape a siege at Hong Kong Polytechnic University

Several dozen parents of the students are holding a vigil outside the campus, hoping to put pressure on the authorities to avoid bloodshed.

One mother in her 50s, whose surname is Chan and whose 18-year-old son remains on campus, said: 'I'm worried when the police go in to attack there will be heavy casualties, a Tiananmen 2.0.'

The massacre China still won't acknowledge: What happened at Tiananmen Square? Events leading up to the massacre at Tiananmen Square began in April 1989, when pro-reform leader Hu Yaobang - who had been ousted as General Secretary of the Communist Party - died. Thousands of students marched to Tiananmen Square in central Beijing to mourn his passing in what evolved into a protest over economic inequality, democracy and freedom of speech. On May 20 the Chinese government declared martial law and sent 250,000 soldiers to Beijing. On June 4, Chinese soldiers entered the square and opened fire on protesters and onlookers without warning, causing mass panic and ending the demonstration. Witnesses recalled people being shot, trampled and crushed to death by military vehicles. At some point on June 5, a protester was filmed standing in front of a column of Chinese tanks before being dragged away by onlookers. The man's identity has never been revealed, and it is not clear whether he survived the massacre. Estimates of the number of dead range between several hundred and several thousand, with thousands more wounded. To this day China has never officially acknowledged the massacre and has not released an official death toll. Advertisement

Meanwhile on campus, protesters were removing metal manhole covers with some making exploratory forays into the fetid tunnels, following rumours of successful escapes from a campus ringed by baton-wielding police.

Pockets of protesters, some with thick bandages wrapped around their knees in anticipation of a long crawl to freedom, knot the holes discussing an unlikely - and highly dangerous - breakout.

AFP reporters saw one group on their stomachs practising crawling. Another group hugged each other in consolation after apparently agreeing not to take the route down into the unknown.

'The people outside can't help us,' a protester told local television as he prepared to descend into a sewer. 'So what can we do?'

One protester, gas mask on, and cling film wrapped around his arms, carried a torch as he descended with his backpack down the metal rungs into the subterranean gloom.

It comes after several dozen students escaped by clambering down ropes dangling from a bridge on campus on Monday night. The students abseiled on to the motorway below before being taken away on motorbikes.

'The rioters... have to stop violence, give up the weapons and come out peacefully and take the instructions from the police,' Ms Lam said.

Hong Kong police spokesman Kwok Ka-chuen says police have not yet decided their next steps to end a standoff at Polytechnic University but are still hoping for a peaceful resolution.

Kwok said at a daily briefing Tuesday: 'We will be closely monitoring the situation, will continue to collect intelligence and decide the next step to take.'

Asked whether a deadline had been set for the anti-government protesters inside to surrender, Kwok gave no specifics. He also did not address reports that the authorities are planning to cut power and water to the campus ahead of a final clearance operation.

Kwok said more than 3,900 gasoline bombs were discovered on another campus, Chinese University, and he expected that large numbers of homemade weapons were also being stored at Polytechnic University.

Some 235 injured were taken to hospital on Tuesday, the Hospital Authority said.

A police officer armed with a rifle is seen on the streets of Hong Kong Tuesday, hours after chiefs said they would be willing to use live ammunition on demonstrators

State-owned Chinese media has also floated the idea of using snipers to take out student demonstrators, leading to fears there could be a massacre

Fears of a Tiananmen Square-style massacre grew in Hong Kong on Tuesday as up to 200 students remained on the campus of the city's Polytechnic University, despite evacuations overnight (pictured, a man is taken for medical treatment)

Hong Kong chief executive Carrie Lam said up to 600 people were evacuated overnight, 200 of them children who were questioned and released, and another 400 adults who were arrested

Exhausted protesters sit wrapped in blankets after leaving the campus of Hong Kong PolyU, where up to 200 remain in a tense standoff with police

Parents of students still trapped on the campus said they feared a 'Tiananmen 2.0' massacre after officers said they would consider using live ammunition against them

Protesters, many of whom were suffering from hypothermia, wait to be treated by medics after leaving PolyU campus. They now face up to 10 years in jail accused of rioting

Injured anti-government protesters are treated by medics at Hong Kong Polytechnic University overnight Monday

Carrie Lam, whose resignation has become a key demand of the protesters, urged those remaining on the PolyU campus to put down their weapons and surrender, saying it is now their only option

China also appointed a new Hong Kong police chief, Chris Tang Ping-keung (left), on Tuesday in a move sure to anger protesters who have been asking for greater autonomy from Beijing

Unwell and injured protesters speak to loved ones on the phone as they wait for medics at Hong Kong Polytechnic University

Protesters wait to receive medical attention after being evacuated from the PolyU campus overnight on Monday

Hundreds of protesters arrived outside campus on Tuesday night and shone their phone lights at police as they prayed for the students trapped inside the university

Protesters hold their illuminated phones in the air during an evening vigil for students who are still trapped on the PolyU campus after a three-day standoff with police

A teacher takes part in protests over police treatment of students trapped inside a university campus in Hong Kong, faced with the prospect of arrest or a potential massacre

Police say they have arrested around 1,100 people in the last 24 hours on charges including rioting and possession of offensive weapons (pictured, protesters holding a vigil near the Poly U campus)

Protesters raise their mobile phones with lights on as they gather to show their support for protersters who are still inside the campus of the Hong Kong Polytechnic University

Police have made about 1,100 arrests in the past 24 hours on charges including rioting and possession of offensive weapons, they said. The total since citywide protests began in June is more than 5,000.

Japan has confirmed that one of its citizens, believed to be a student who was visiting Hong Kong as a tourist, is among those arrested.

Meanwhile Chinese foreign ministry spokesman Geng Shuang slapped down US Secretary of State Mike Pompeo after he gave his backing to the students, accusing America of double standards.

Geng said Tuesday that while the U.S. has 'appeared to be fair' concerning pro-democracy protests in Hong Kong, it harbors 'ulterior intention to intervene ... and double standards on violent crimes.'

Geng said efforts by Hong Kong police to enforce the law should not be compared to the violent behavior of 'extremist forces.'

The UN Human Rights office also expressed concern about the situation at the university, urging authorities to do all the can to deescalate.

A spokesman for the United Nations High Commissioner for Human Rights, Rupert Colville, said he is concerned about increasing violence by young people 'who are clearly very angry, with deep-seated grievances.'

Colville told reporters in Geneva that most protesters have been demonstrating peacefully, and that authorities had 'by and large' respected the right to freedom of assembly.

He urged Hong Kong authorities to 'address the humanitarian situation' of protesters at Polytechnic University whose situation was 'clearly deteriorating.'

Elsewhere on Tuesday, China appointed a new police chief in Hong Kong, a move sure to anger protesters who have been asked for greater autonomy from Beijing.

The new chief, Chris Tang Ping-keung, said rebutting fake accusations against police and reassuring the public about the force's mission would be among his priorities.

He said following a ceremony Tuesday morning: 'We have to maintain the law and order in Hong Kong and there is a massive scale of breaking of law in Hong Kong and there is a certain sector of the community that also condones those illegal activities.'

Tang has been on the police force for more than 30 years and takes over from Lo Wai-chung, who is retiring after 35 years of service.

An anti-government protester walks past a fire on a bridge at one of the entrance that leads into the Hong Kong Polytechnic University. Activists have used the blazes to keep police off the campus

Firemen put out a burning car set on fire by protesters near Hong Kong Polytechnic University in an attempt to draw security services away from the campus and allow students to escape

Firemen put out a burning car set on fire by protesters near Hong Kong Polytechnic University

Protesters clash with police when they try to move to Hong Kong Polytechnic University to rescue other protesters surrounded by police

Hong Kong's police spokesman said Tuesday that officers had not yet decided on the next step towards ending the campus stand-off, but said they were still hopeful of a peaceful conclusion

Protesters from outside the university have gathered at the police cordon and were facing off against officers on Tuesday in the hopes of preventing further violence

Police officers confront protesters during an anti-government protest in Hong Kong

Family members of students barricaded inside Hong Kong Polytechnic University hold up signs during a protest

Protesters leave from the main entrance to Hong Kong Polytechnic University campus as they surrender to police

Protesters make their way around a makeshift barricade at Hong Kong Polytechnic University to surrender to police

An injured youth sits under a space blanket at a casualty evacuation point near Hong Kong Polytechnic University

People wearing face masks duck down as they walk at Hong Kong Polytechnic University in Hong Kong

A young man carries an injured young woman to an ambulance as some protesters under the age of 18 leave from the Hong Kong Polytechnic University overnight Monday

Ingredients used to make Molotov cocktails as well as a form of napalm that was used by students to keep the police at bay is seen inside Hong Kong Polytechnic University

University authorities had previously said that students had stolen chemical stores and were using them to make weapons to be used against the authorities

Police said they found almost 4,000 gas canister bombs at the site of another university protest, and expected to find more inside PolyU when the campus is finally cleared (pictured, ingredients for petrol bombs)

A makeshift bow was among objects left behind by students in the canteen at PolyU after they surrendered following a three-day standoff with police

A plastic skull is seen on top of a pole at the PolyU campus, where between 100 and 200 students are thought to be holed up

A view of the gymnasium inside the Polytechnic University where some of the student protesters had been sleeping after a three-day stand off between activists and police

Graffiti covers part of the badly damaged canteen inside Hong Kong's PolyU, which has been the site of major clashes between pro-democracy protesters and police

The Hong Kong government said Tang's appointment was made 'on the recommendation and nomination' of Chief Executive Carrie Lam, but with the final approval of the State Council, or Cabinet, in Beijing.

Also on Tuesday, a Hong Kong court rejected an appeal by pro-democracy protester Joshua Wong - who was arrested during the 2014 umbrella protest - to change his bail conditions so he can travel abroad.

Hong Kong's High Court denied Wong's application to leave the territory, citing the risk that he won't return.

Demosisto, a pro-democracy group that Wong founded, said he was invited to speak in several European countries including France, Italy and Germany. The court said Wong can give his talks through video recordings.

Students have been taking part in pro-democracy protests at the university for almost a week, but scenes turned ugly overnight Sunday as riot officers tried to storm in and were met by volleys of napalm bombs and arrows as concourses were set alight to keep them out.

Police were accused of using a 'sonic weapon' mounted on top of a truck to make activists sick and disoriented - which they denied - while pictures emerged of what appeared to be a gas canister bomb seized from students.

Hundreds of panicked and exhausted activists began trying to escape the campus on Monday morning, but were met by tear gas, rubber bullets and police batons. Many were arrested, and now face up to 10 years in jail for taking part in what Hong Kong's rulers have deemed a riot.

Students trapped on the Hong Kong Polytechnic University campus by police staged a daring escaped by scaling down ropes attached to a bridge and on to a motorway below, before being taken away on bikes

Students fled the university campus amid fears of a bloodbath after police commanders threatened to start using live ammunition after a night of violent clashes on Sunday

Protestors use a rope to lower themselves from a pedestrian bridge to waiting motorbikes in order to escape from Hong Kong Polytechnic University and the police

Students used napalm bombs and bows and arrows against police on Sunday in the worst night of violence of Hong Kong's protests, prompting many to try and flee on Monday before a feared retribution takes place

Despite the breakout there are thought to be hundreds of people still trapped on the PolyU campus, where they have been protesting for a week demanding democratic reforms in the city-state

Protesters run towards motorcyclists after lowering themselves down a rope from a bridge to a highway, to escape from Hong Kong Polytechnic University campus

Students are carried on to motorbikes and driven away from Hong Kong Polytechnic University after escaping off a bridge

As the students tried to escape, more demonstrators clashed with police in other areas of the city, attempting to draw officers away from the campus and provide the activists with a window of opportunity

Anti-government protesters shoot arrows at the police from the Hong Kong Polytechnic University campus

Police deploy a water cannon to disperse protesters attempting to march towards Hong Kong Polytechnic University

Pro-democracy protesters march on Salisbury Road towards Polytechnic University as they attempt to draw out police and provide time for students trapped there to escape

Protesters march towards PolyU, which has become a focal point of the six-month-long Hong Kong pro-democracy protests and the scene of some of the most violent clashes so far

Police fire tear gas to protesters in the Kowloon area of Hong Kong, a short distance from the university, on Monday evening

As night fell in Hong Kong, police tightened a siege Monday at a university campus as hundreds of anti-government protesters trapped inside sought to escape

Images circulated on Monday of what appeared to be a gas canister bomb embedded with shrapnel to be used against police trying to clear students out of Hong Kong PolyU

Police were accused of using a 'sonic weapon' against protesters (pictured mounted on top of this truck) designed to make them sick and disoriented, although officers denied this, calling it a long-range microphone

Protesters form a human chain to pass items to the frontline during clashes with police as they attempt to march towards Hong Kong Polytechnic University

Protesters form a human chain to pass items to the frontline during clashes with police

Dozens of Hong Kong protesters escaped a two-day police siege at a campus late on November 18 by shimmying down a rope from a bridge to awaiting motorbikes in a dramatic and perilous breakout

Protesters retreat during clashes with police as they attempt to march towards Hong Kong Polytechnic University in Hung Hom district of Hong Kong

No turning back: A pro-democracy protester in Hong Kong uses a road sign as a shield during clashes with police

Protesters gather at the Jordan area in Kowloon district as they march towards Hong Kong Polytechnic University

Demonstrators flooded back into other parts of the city on Monday in an attempt to draw the stretched police force out and allow the students an exit.

Police fired tear gas in the Kowloon area of the city, as protesters used umbrellas to deflect the canisters and fires burned in the streets.

Senior government officials said they were trying to de-escalate the situation and urged the protesters to peacefully leave the campus and cooperate with police - advice that seemed certain to lead to arrests and therefore strengthened the protesters' resolve to resist.

Beijing will not sit back and simply watch if the protests in Hong Kong become 'uncontrollable', China's ambassador to Britain Liu Xiaoming warned at a London news conference on Monday.

'If the situation becomes uncontrollable the central government would certainly not sit on our hands and watch,' he told reporters in London, adding: 'We have enough resolution and power to end the unrest.'

Police fire tear gas at students attempting to escape from Hong Kong Polytechnic University on Monday, following a night of violent clashes that saw police officers shot with bows and arrows

Hundreds of students are now trapped on the university campus, where some have been protesting for up to a week over China's control over Hong Kong. Pictured are some students being led away by police

Students spent the night Sunday trying to stop officers entering the campus, but after hours of intense clashes many exhausted activists were desperate to leave and attempted to flee (pictured, captured students are led away)

Groups of protesters from outside the university also attempted to get inside to let the students escape, and were confronted by police wielding batons and firing rubber bullets

A protester who appears to have been shot in the head by a rubber bullet fired by police is placed on a stretcher and taken away from Hong Kong PolyU, which has been the site of intense clashes

Medical staff carry a protester out of the campus of Hong Kong Polytechnic University (PolyU) during clashes with police

A fire set by protesters burns at the Hong Kong Polytechnic University campus in Hong Kong. Staff say a number of chemicals have been stolen by demonstrators and the campus has been heavily damaged

An anti-government protester puts out a fire at Hong Kong Polytechnic University amid clashes with police

Protesters stand on the steps of the Hong Kong Polytechnic University after large parts of the campus were set on fire to prevent officers from entering overnight Sunday

Protesters outside the university hold up British and American flags along with a sign reading 'save us' outside the university

The Asian financial center's work week began Monday with multiple protests that disrupted traffic, while schools remained closed because of safety concerns stemming from the demonstrations.

Beijing 'will not sit on our hands if situation becomes uncontrollable' Beijing will not sit back and simply watch if the protests in Hong Kong become 'uncontrollable', China's ambassador to Britain Liu Xiaoming warned at a London news conference on Monday. 'If the situation becomes uncontrollable the central government would certainly not sit on our hands and watch,' he told reporters in London, adding: 'We have enough resolution and power to end the unrest.' China's ambassador to Britain has accused the U.K. and U.S. of interfering in the internal affairs of China and Hong Kong as authorities in the semi-autonomous territory struggle to contain months of protests. Liu Xiaoming told reporters in London on Monday that reports by the British government and Parliament's foreign affairs committee included 'irresponsible remarks' criticizing how the Hong Kong government and police have handled the protests. Liu said, 'they look like they are balanced but as a matter of fact they are taking sides.' Advertisement

The protests began in June over a now-defunct bill that would have allowed deportation to mainland China, but have become increasingly violent in recent weeks.

The pitched battle for control of the campus of Hong Kong Polytechnic University has been the center of the most recent developments.

For days, protesters have fortified the campus to keep out the police. Now cornered by police determined to arrest them, they desperately tried to get out but faced a cordon of officers armed with tear gas and water cannons.

An editorial published in the South China Morning Post, which has links to the regime in Beijing, on Monday described the activists as 'hardcore mobs' while warning the city is 'on the brink of total breakdown'.

Anti-government protesters barricaded themselves inside Polytechnic last week. Police surrounded the area on Sunday night and began moving in after issuing an ultimatum for people to leave the area.

The crowd wore raincoats and carried umbrellas to shield themselves from police water cannons.

Riot officers broke in one entrance before dawn as fires raged inside and outside the school, but they did not appear to get very far.

Riot police fired tear gas and rubber bullets at protesters trying to flee the campus of Hong Kong Polytechnic University on Monday morning, after a night of violent clashes

A group of around 100 demonstrators tried to escape the campus at daybreak on Monday, aided by a second group which moved in from outside the police cordon in an attempt to break their lines and allow trapped activists to slip away

Protesters spent most of the night trying to stop police getting into the university but by morning, with many of them exhausted and injured, a large group was trying to escape with help from outside (pictured an arrested protester)

Police have warned that they may start using live ammunition against demonstrators after officers were hit by hails of arrows and petrol bombs overnight, raising fears of widespread bloodshed

Despite earlier reports of a truce between student demonstrators and police at Hong Kong PolyU to allow people to leave, officers fired tear gas and used batons on anyone attempting to flee campus on Monday

Dozens of people were arrested early on Monday with police using batons against people that had fallen to the ground, and kicking some handcuffed activists

Police in riot gear detain protesters amid clouds of tear gas at the Hong Kong Polytechnic University after the worst night of violence in almost six months of demonstrations

A riot police officer points a gun at protesters attempting to escape the campus of Hong Kong Polytechnic University. Chiefs confirmed on Monday that live rounds have been fired, but said nobody had been hit

Fiery explosions were seen as protesters responded with petrol bombs. Police, who have warned that everyone in the area could be charged with rioting, reportedly made a handful of arrests.

Hong Kong's anti-mask law overturned by court The High Court of Hong Kong has ruled that an emergency law introduced by the government to ban protesters from wearing masks in public is 'unconstitutional'. The law went into effect last month after the government invoked colonial-era emergency powers to curb escalating violence sparked by ongoing anti-government demonstrations. The court claimed that the legislation 'goes further than necessary' to restrict fundamental human rights. The ruling came after a group of 24 pan-democrats submitted a petition to the court to challenge the legitimacy of the anti-mask law as well as The Emergency Regulations Ordinance that backs it. The decision was handed down today in a 106-page document. The High Court also declared that the emergency ordinance was 'incompatible with the Basic Law' because it gave the city's Chief Executive power to pass laws and regulations 'on any occasion of public danger'. The Basic Law is Hong Kong's mini-constitution which governs its relations with Beijing. Advertisement

Shocking footage showed the moment anti-government protesters hurling petrol bombs alight and causing a police truck to burst into flames.

Police have now declared events at PolyU a 'riot' - meaning participation is punishable by up to 10 years in jail.

Fear gripped protesters inside the campus - whose occupation is a twist in tactics by a leaderless movement so far defined by its fluid nature.

One 19-year-old, who gave her name as 'K', said there was desperation among those who remained.

'Some people were crying badly, some were furious, some agonising, because they felt hopeless as we were left no way out of the campus.

'We don't know when the police will storm in.'

Protests erupted in several other parts of peninsula Hong Kong, with makeshift barricades across normally bustling shopping streets, the road surfaces strewn with bricks to hamper vehicles.

Police fired tear gas at groups who had gathered in the Tsim Sha Tsui and Jordan areas, where they also made a number of arrests.

The unrest has rocked previously stable Hong Kong, tipping the international financial hub into recession and frightening off tourists.

What began as a series of huge, peaceful demonstrations against a now-shelved bill to allow extradition to the Chinese mainland has morphed into calls for democracy and an inquiry into police behaviour.

Violence has worsened this month, with two men killed in separate incidents.

Hong Kong police fought off protesters with tear gas and batons Monday as they tried to break through a police cordon that is trapping hundreds of them on a university campus

A policeman in riot gear points his weapon as protesters try to flee from the Hong Kong Polytechnic University in Hong Kong early on Monday, following a night of violent clashes

Anti-government protesters clash with police at Hong Kong Polytechnic University as they attempt to break through a police cordon around the university and escape, after a night spent trying to keep officers out

Police were seen making dozens of arrests on Monday morning as people tried to escape the university, aided by those on the outside who were trying to help them

Officers in riot gear fire tear gas and rubber bullets at students attempting to break out of Hong Kong PolyU after a night of extraordinary violence between demonstrators and police

Hong Kong police fought off protesters with tear gas and batons Monday as they tried to break through a police cordon that is trapping hundreds of them on a university campus

Police could be seen dragging protesters to the floor on Monday as they used batons and boots to subdue them

Officers corner and arrest students fleeing from Hong Kong PolyU after declaring the situation on campus a riot, meaning anyone participating can be punished with up to 10 years in jail

Students carrying umbrellas and upturned tables to protect against police tear gas canisters attempt to leave the campus of Hong Kong PolyU after an night of intense clashes

A female protester is dragged away by riot officers as others are tackled to the floor and arrested following a night of violence

Exhausted demonstrators collapse on the floor inside the university campus after a night of fierce clashes with police

While student activists spent the night trying to keep police off the campus of Hong Kong PolyU, by daybreak many of the exhausted demonstrators were trying to leave, but prevented from doing so

Anti-government protesters flee from the police at Hong Kong PolyU after a night of violence which saw arrows fired at police, and some officers use live ammunition in return

Riot police move in to arrest demonstrators as they try to escape from Hong Kong PolyU in the early hours of Monday