Flights have been cancelled at Hong Kong's worldwide airport as thousands of anti-government protesters flooded the building.
Mass protests at Hong Kong's worldwide airport have forced flight cancellations to and from Australia.
"Youngspiration hereby urge governments of the world and all freedom-loving people on Earth, to stand against China, the Enemy of Humanity, and its executioners, the Hong Kong Police Force and the incompetent Carrie Lam government", it said.
"One must take resolute action toward this violent criminality, showing no leniency or mercy", the statement read.
Only flights that had already started boarding or those cleared for landing were allowed to use runways at the airport.
Hong Kong airport authorities worked to resume flights after a shutdown it blamed on demonstrators, while China said anti-government protests that have swept the city had begun to show "sprouts of terrorism".
All flights departing flights from the airport - one of the busiest in Asia - have been canceled after 5:50 p.m. local (5:50 a.m. ET).
Some protesters were seen walking toward the airport amid the stifling heat.
"Members of the public are advised not to come to the airport".
"Hong Kong's radical demonstrators have repeatedly used extremely unsafe tools to attack police officers, which already constitutes a serious violent crime, and also shows the first signs of terrorism emerging", Yang Guang, spokesman for the Hong Kong and Macao Affairs Office of the State Council, said on Monday. The young man, who said his name was Chow Ka-lok and asked for a lawyer, was shown with a bleeding head wound and said he had a broken tooth.
Police have also reported injuries among their ranks, including eye irritation from laser pointers, burns from petrol bombs and bruises and cuts from flying. Thousands flocked to the airport to protest police brutality they said was committed during anti-government protests over the weekend.
Adding to the protesters' anger, Hong Kong's Cathay Pacific Airways told employees in a memo that the carrier has a "zero tolerance" for employees joining "illegal protests" and warned disciplinary consequences could include being fired.
Inside a metro station in Kwai Fong, which is located in the New Territories, police charged at protesters and fired rubber bullets at point-blank range.
Police stormed a number of underground train stations, firing tear gas and arresting protesters. Many wore face masks to shield their identities, and a few had helmets.
Protests in Hong Kong have continued to escalate, despite their primary cause - an extradition treaty bill with mainland China - already having died.
Hong Kong police are resorting to harsher tactics as they struggle to control the mass protests.
For a fourth straight day on Monday, thousands of activists peacefully occupied the arrivals hall at Hong Kong's busy airport, shouting, "No rioters, only tyranny!"
"For the CIA's hand to be openly involved in formatting dissent within other nations doesn't look good, so they started this private non-profit, which is mostly funded by the USA government, to do the same work that during the Cold War had been done by the CIA", Wong explained. "We have to come here to protest", Lau said. But Hong Kongers have long accused Beijing of encroaching on this autonomy since the handover, spurring protests and unrest.
Ly said that they arrived at the airport a few hours early and checked in through security before they saw that it was cancelled on the departures board.