Overnight, the airport’s management obtained an interim injunction “to restrain persons from unlawfully and wilfully obstructing or interfering” with airport operations.
About three dozen protesters have remained camped inside the arrivals area, but said they would obey the injunction. Workers had to scrub the port clean of blood and debris.
Check-in counters reopened to queues of hundreds of weary travellers at one of the world’s busiest airports.
Dicky, a 35-year-old protester who has been there for more than two days, said: “We will continue to fight for what we deserve otherwise all of that would have been in vain.”
Weeks of protests have plunged Hong Kong into its worst crisis since it reverted from British to Chinese rule in 1997.
US President Donald Trump said Chinese troops were moving toward the border and urged calm, as the Hong Kong and Macau Affairs office warned that violent crimes would be punished severely.
On Twitter, Mr Trump wrote: “Our intelligence has informed us that the Chinese Government is moving troops to the Border with Hong Kong. Everyone should be calm and safe!”
“These atrocities, which are lawless, trampling on human rights and inhumane, have completely gone beyond the bottom line of civil society, and is no different to terrorists,” China’s Liaison Office in Hong Kong said in a statement.
Travel was suspended from the airport on Tuesday, with 120 flights cancelled, as thousands of demonstrators, many wearing black and covering their faces, barricaded entrances with luggage trolleys.
Flag carrier Cathay Pacific took out a half-page advert in the Hong Kong Economic Journal, pledging its support to the government and calling for the restoration of rule of law and social order.
At the peak of Tuesday’s violence, officers swinging batons and armed with pepper spray entered the terminal, with a policeman pulling out a gun at one point.
The police seemed overwhelmed at times – and were pelted with bottles as they tried to restore order.
Sky’s chief correspondent Stuart Ramsay, who was at the scene, said: “Eventually riot police were deployed to help police buses full of officers get away as they were being attacked and they were dangerously close to getting their doors kicked in.”
Protesters beat up at least two men they suspected of being undercover agents – and of one of them was tied to a trolley as activists rifled through his bag.
It took two hours for paramedics to reach the bound man, who was hurried into an ambulance after a “tug-of-war battle”. The editor-in-chief of the pro-China Global Times newspaper later said he was one of their journalists, and not a police officer.
The protests began over a controversial law that would allow suspects to be sent to mainland China. Demonstrators want that extradition bill to be scrapped, amid fears that suspects could face torture or unfair, politically charged trials.
Protesters are also calling for the resignation of Carrie Lam, Hong Kong’s leader.
She has warned that the continuing instability, chaos and violence have placed the city on a “path of no return”.
Foreign Office minister Andrew Murrison said on Tuesday evening he is “very concerned” about the situation, calling the scenes from the airport over the past few days “deeply troubling”.
With Beijing reportedly planning a crackdown, he said: “I don’t think it’s in the interests of anybody to take a hard line. It’s in everybody’s interests to try to turn the temperature down on this.”