Police earlier threatened to use live rounds on ‘rioters’ who used lethal weapons such as molotov cocktails against them

Hong Kong police have laid siege to the city’s Polytechnic University, where about 200 protesters are holed up after a weekend of violence which saw conflict between the two sides reach new heights.

Protesters tried to leave the campus on Monday morning – at the request of the university’s president – but were forced back by police who fired rounds of tear gas. Explosions and gun fire could be heard in videos posted online showing the protesters attempting to leave the area.

Hong Kong protest: police fire rounds of tear gas at protesters trying to leave campus – live Read more

The tactics used by police raised fears that the authorities had no interest in de-escalating the situation, but were aiming to trap and arrest all protesters.

Dozens of people who were not involved in the siege have been arrested in the street after asking police to lift the siege, Hong Kong Free Press reported.

On Monday morning, police attempted to storm the university in Kowloon after a 24-hour battle with protesters which saw officials threaten to use live rounds. Earlier, officers fired teargas and water cannon and drove an armoured vehicle at demonstrators who threw molotov cocktails. The police said in a video statement they would use live rounds on the “rioters” if they did not stop using lethal weapons to attack officers.

As riot police moved in at dawn, protesters set fire to one of the entrances to the university and explosions could be heard. The blazes forced police to pull back.

Professor Teng Jin-guang, the president of Poly U, released a video statement on Monday saying he had negotiated a temporary suspension of the use of force with the police and urged protesters to “leave the campus in a peaceful manner”. When they did so, they were forced back by tear gas.

Tom Cheshire (@chesh) Reports police are now here inside #PolyU. Protestors setting huge fires at one entrance pic.twitter.com/CT0JFepzF2

During the day on Sunday, the university, which has been taken over by protesters since clashes last week, became the site of some of the longest, tensest clashes between anti-government demonstrators and police of the last five months.

As a helicopter hovered overhead, riot police shot blue-dyed liquid laced with pepper spray at protesters who set fire to a pedestrian bridge packed with furniture, umbrellas and other materials, causing a blaze that was later put out by firefighters. Protesters on part of the university’s roof used catapults as well as bows and arrows to shoot at police, with one arrow striking an officer in the calf.

They also occupied a flyover and threw petrol bombs at riot police, setting off explosions and sending flames into the sky. An armoured vehicle drove towards protesters but was stopped by a barricade and pelted with molotov cocktails until it caught fire.

“The main goal is to protect the campus and prevent people from getting arrested,” said Rudy Lau, 27, an alumnus of the university. Using binoculars, he monitored a group of police outside the grounds, and alerted others to their movements.

Support for Hong Kong’s rebels wavers after most violent week yet Read more

“People are trying everything. Most of the actions we do are indeed pointless because the Chinese government is not budging. So we just have to try to do everything and keep the momentum going,” he said.

Owen Li, a PolyU council member and student, said “panic” had taken hold of the estimated few hundred protesters who remained. “Many friends feel helpless … we appeal to all of society to come out and help us.”

Thousands of residents and protesters flocked to various districts around the university to try to penetrate the riot-police lines to rescue the trapped students.

“If we can only hold on till dawn, more might come,” said one young activist in the university who was close to exhaustion.

By late evening on Sunday, the unrest had spread, as protesters and their supporters took to the streets in at least five other locations to draw police resources away from the university. Hundreds of protesters gathered in Jordan, also in Kowloon, and lit a barricade as police pursued them with teargas and water cannon.

Volunteers also parked their cars in the middle of roads leading to the university, prompting the police to issue a statement ordering drivers not to block the roads and obstruct a police operation.

At the university, dozens were arrested as they tried to leave, following a police order to evacuate by a specified exit.

The confrontation, a continuation of the fighting from the night before, began in the morning when protesters were seen throwing bricks at residents trying to clear a blockaded road. It continued into the late evening, when police declared the unrest a riot and warned that anyone who remained on the campus or assisted the perpetrators would be considered a rioter.

Facebook Twitter Pinterest The university said it was ‘gravely concerned’ by the unrest. Photograph: Ng Han Guan/AP

The university issued a statement calling on people to leave the grounds immediately. “The university is gravely concerned that the spiralling radical illicit activities will cause not only a tremendous safety threat on campus, but also class suspension over an indefinite period of time,” it said.

Political unrest has escalated dramatically in the last week as demonstrators have blocked transport links and roads and paralysed parts of the city. After the Chinese president,Xi Jinping, delivered his first public remarks on the crisis on Thursday after five months of protests, People’s Liberation Army soldiers took to the streets on Saturday to help residents clear blocked roads.

Play Video 0:59 Hong Kong: China deploys troops to remove roadblocks at university – video

Dressed in shorts and T-shirts and holding plastic buckets, the soldiers helped residents clear the protesters’ improvised barricades, a move that demonstrators described as “clearance today, crackdown tomorrow”. The Hong Kong government said it had not requested the help, describing the soldiers’ excursion as a “voluntary activity”.

On Sunday, Chinese soldiers at a base near the university, some in riot gear, were seen monitoring the situation. The Global Times reported that police in Guangzhou were holding “counter-terrorism” exercises.

The smell of teargas wafted over the campus, which has been turned into a battle station as first aid volunteers tended to injured protesters and others sorted supplies and prepared molotov cocktails. Protesters struck by the water were stripped and hosed down.

Activists have destroyed the tollbooths along the tunnel and built barricades on the road, blocking a major traffic artery. Roads leading into the university were strewn with bricks and nails in an effort to slow police. Heeding calls, dozens of supporters had arrived and were pulling up more bricks.

“I really support them. I’ve joined every demonstration from 9 June to now,” said Lee, 68, a retired police officer who was helping arrange bricks. “They are boiling the frog alive,” he said, referring to China’s growing control over Hong Kong.

After almost six months of weekly and now daily protests, Hong Kong’s crisis reached a new peak last week after two protest-related deaths, dozens of injuries, and what were seen as attacks on universities by the police.

Facebook Twitter Pinterest A fire burns at Polytechnic University. Photograph: Ng Han Guan/AP

Residents have become frustrated and impatient with the traffic disruptions, while others have grown alarmed by what they see as the protesters’ increasing violence and intolerance for those who disagree with them.

Hong Kong’s education bureau has called off lessons on Monday, after cancelling classes on Thursday and Friday out of safety concerns. Several universities have ended the semester early and sent foreign students home.

On Sunday, Hong Kong’s finance minister, Paul Chan, said the city was heading towards its worst recession since the 1997 handover, as tourist numbers have fallen, and stocks and retail sales have been hit.

Calvin See, 27, who works at a logistics company, said the disruptions and slowdown were hurting its revenues. He had come to help support the protesters at Polytechnic University after seeing calls for reinforcements.

“That’s not the worst part. I worry about people getting hurt, people getting shot. If I lose my job, I’m not going to die,” he said. “Those people on the front, they are putting their lives on the line to fight for what they believe … they are doing it for all of us.”