Frenzied mob violence against two male protesters suspected of being spies from mainland China marked the second day of pro-democracy demonstrations that have caused mass cancellations and disruptions in Hong Kong’s busy airport.

Calm eventually returned, with most of the protesters leaving the airport hours after officers armed with pepper spray and swinging batons tried to enter the terminal, fighting with demonstrators who barricaded entrances with luggage carts.

Check-in counters have reopened at Hong Kong’s airport after being shut during protests the previous day.

About three dozen protesters remained camped out in the arrivals area this morning. Flights appeared to be operating normally.

Riot police clashed briefly with the demonstrators, who said they planned to return to the airport early Wednesday local time.

The airport says it has an injunction to restrain protesters.

Hong Kong police tweeted that a visitor was “besieged” by protesters, who they believed was an undercover cop.

Protesters cable-tied the man’s hands and claimed to have found his name on an online list of police officers in southern Guangdong province. Police used pepper spray to get past the protesters and get the man to hospital.

Protesters also detained a second man who they suspected of being an undercover agent.

After emptying out his belongings, they found a blue T-shirt that has been worn by pro-Beijing supporters that they said was evidence he was a spy.

As with the first man, some protesters tied his wrists together and poured water over his head, inciting laughter from some in the crowd.

Airport security appeared unable to control the crowd.

Hu Xijin, editor-in-chief of the Global Times, a nationalistic Chinese tabloid, said the man was one of his reporters.

“Fu Guohao, reporter of GT website is being seized by demonstrators at HK airport,” Hu wrote on his widely followed Twitter account.

“I affirm this man being tied in this video is the reporter himself. He has no other task except for reporting.”

One protester used a US flag to beat Fu as he lay on the floor in a foetal position.

Other protesters and first aid workers attempted to stop some who tried to trample the man, while pro-democracy politician Kwok Ka-ki crouched beside him and tried to calm the attackers.

After a heated argument, protesters eventually allowed ambulance workers to take the man away on a stretcher.

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Hong Kong police said they arrested five people for unlawful assembly, assaulting police officers and possessing weapons.

Police have acknowledged using “decoy” officers, and the violence followed weekend sightings of men dressed like demonstrators — in black and wearing face masks — appearing to arrest protesters.

The airport closed check-in for remaining flights late Tuesday afternoon as protesters swarmed the terminal and blocked access to immigration for departing passengers.

More than 100 flights were cancelled on Tuesday, the fifth consecutive day that protesters occupied the airport.

Airlines were still working through a backlog of more than 200 flights from Monday when the airport announced in the afternoon that check-in processes would once again be suspended.

“Democracy is a good thing,” said signs that appeared to be aimed at mainland Chinese and foreign travellers.

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Many signs also contained apologies for the disruption to travellers: “We stand here to obstruct, only for one single reason. We love and care for Hong Kong. We hope you will understand. Sorry.”

Officials said in a statement that some protesters detained, harassed and assaulted a traveller and a journalist, and obstructed ambulance workers from taking the two men to the hospital. They said other protesters attacked a police officer and snatched a baton from him.

Meanwhile, US President Donald Trump has claimed that his intelligence sources have told him that the Chinese Government is moving troops to the border with Hong Kong.

“Everyone should be calm and safe!” he wrote on Twitter.

“Many are blaming me, and the United States, for the problems going on in Hong Kong. I can’t imagine why?”

Chinese state and social media had earlier aired video of security forces gathering across the border from the enclave, which has been rocked by unrest for ten weeks.

The Global Times and the People’s Daily ran a minute-long video compiling clips of armoured personnel carriers and troop carriers purportedly driving to Shenzhen, which borders Hong Kong.

The video shows roughly two dozen armoured carriers apparently driving through the southern city of Guangzhou and other troop carriers leaving eastern Fujian province.

Hu Xijin, editor-in-chief of the state-run Global Times, said on social media that the military presence is a sign that if the situation in Hong Kong doesn’t improve, China will intervene.

Speaking to reporters in Morristown, New Jersey, Mr Trump called the situation in Hong Kong “very tricky.”

“I hope it works out peacefully, nobody gets hurt, nobody gets killed,” he said.

Hong Kong Kung Fu star Jackie Chan expressed his loyalty to the Communist Party in China as the protests continued.

Chan, who has long been a pro-Beijing loyalist, told China’s state broadcaster CCTV that

“On one hand, (I) needed to express my most basic patriotism as a Hong Kong and Chinese citizen. I am one of the flag guards.,” he said.

“Hong Kong is my birthplace and my hometown. China is my home country,” he said. “I love my country. I love my hometown. I truly hope peace can return to Hong Kong as quickly as possible.”

FLIGHTS CANCELLED

Hong Kong’s airport has cancelled all remaining flights for the second day after protesters took over the terminals.

Immigration counters have shut down after protesters blocked the entrance.

Pro-democracy protesters moved into the departures hall at Hong Kong International Airport for a fresh rally.

Flights were suspended yesterday after people occupied the site.

The latest cancellations come after Hong Kong’s last British governor Chris Patten cautioned that if China intervenes in Hong Kong it will be a catastrophe and Chinese President Xi Jinping should see the wisdom of trying to bring people together.

Chris Patten said it was counter productive of the Chinese to warn of “other methods” if the protests did not stop.

“That would be a catastrophe for China and of course for Hong Kong,” Mr Patten told BBC radio.

“Since President Xi has been in office, there’s been a crackdown on dissent and dissidents everywhere, the party has been in control of everything.”

Mr Patten said British Prime Minister Boris Johnson should ask US National Security Adviser John Bolton who is in London this week, to get Washington to agree that it would be a “catastrophe” if China was to intervene in Hong Kong.

Travellers in Hong Kong’s airport voiced support for pro-democracy demonstrators today, despite an overnight occupation of the international transit hub that saw tens of thousands of passengers stranded.

The airport, one of the busiest in the world, reopened this morning but hundreds of flights remained cancelled and several hundred protesters returned for a fresh rally this afternoon.

Monday’s abrupt closure came 10 weeks into a crisis that has seen millions of people take to Hong Kong’s streets in the biggest challenge to Chinese rule of the semi-autonomous city since its 1997 handover from Britain.

“It may affect me, but I still know what they are doing and I support them so it doesn’t matter, said 27-year-old advertising worker Mag Mak, whose flight back home to Hong Kong from Dubai was delayed by five hours.

“I think the government is so rubbish and they don’t have any response to the protesters,” she added.

Some passengers at the airport took a less forgiving view of the occupation. The nationalistic Chinese tabloid the Global Times tweeted footage of one irate Australian passenger who confronted young demonstrators and told them to “go get a job”.

Others told AFP they were angry at having their travel plans frustrated. “I don’t mind what they [the protesters] do but they made us five hours delayed,” said 50-year-old Wing Au-yeung, who had stopped off in the city to collect his aged mother before travelling to South Korea with his family.

“They can do what they want but it should not affect other people.”

As the crisis worsened, there were fears “something extraordinarily bad is about to happen” after a convoy of military-style vehicles was filmed amassing across the border from Hong Kong.

Video posted on Twitter by senior political Adviser at Renew Europe, Alexandre Krauss, purports to show dozens of trucks in Shenzhen, China.

Earlier Krauss posted another video describing the situation.

“The Chinese military, believing in the intel and these videos, have set in place a comprehensive military operation targeting the situation in #HongKong,” he said.

The Chinese military, believing in the intel and these videos, have set in place a comprehensive military operation targeting the situation in #HongKong. #HongKongProtests #China #Democracy pic.twitter.com/QWFM11XYKC — Alexandre Krauss (@AlexandreKrausz) August 12, 2019

The footage was released by the Chinese government.

The state-run People’s Daily did not comment on the purpose of the vehicles, but noted that the People’s Armed Police are in charge of “handling riots, turmoil, seriously violent, criminal activities, terrorist attacks and other societal security incidents”.

The footage was aired on Chinese state TV and came hours after Beijing authorities slammed Hong Kong’s pro-democracy movement, linking them to “terrorism”.

“Hong Kong’s radical demonstrators have repeatedly used extremely dangerous tools to attack police officers, which already constitutes a serious violent crime, and also shows the first signs of terrorism emerging,” said Yang Guang, spokesman for the Hong Kong and Macao Affairs Office of the State Council.

“This want only tramples on Hong Kong’s rule of law and social order.”

Some Hong Kong legal experts say the official description of terrorism could lead to the use of anti-terror laws.