Photos show youths wandering the campus, with some preparing Molotov cocktails while others sleep on a gym floor.
The United States House of Representatives on Wednesday passed two bills intended to support protesters in Hong Kong and send a warning to China about human rights, as dozens remained holed up in a Hong Kong university surrounded by police.
The bills now go to the White House for President Donald Trump to sign or veto amid sensitive trade talks with Beijing.
The House voted 417 to one for the “Hong Kong Human Rights and Democracy Act”, which had passed the Senate unanimously on Tuesday. Strong support for the measure had been expected, as House members passed a similar bill last month.
The legislation, which has angered Beijing, would require the State Department to certify at least once a year that Hong Kong retains enough autonomy to qualify for the special US trading consideration that helped it become a world financial centre
It also would provide for sanctions against officials responsible for human rights violations in Hong Kong.
Demonstrators in Hong Kong have taken to the streets since June angry at what they see as Chinese meddling in the freedoms promised to Hong Kong when the UK returned the territory to Chinese rule in 1997.
Increasing violence in a week when abouy 1,000 protesters occupied a university campus and fought back against police with petrol bombs and other improvised weapons has raised concern that Beijing will ratchet up its response to stop the civil disobedience.
Around 100 remain hunkered down in the Polytechnic University, in the bustling district of Kowloon, after police sealed off the campus saying they will arrest all those inside.
Al Jazeera’s Sarah Clarke, reporting from the police lines, said those inside the campus were frightened and hungry, but also scared to leave.
In an editorial on Wednesday after the Senate approved the bill, China’s Global Times said the legislation “tarnished sacred terms” like human rights and democracy.
“The bill’s real title should be “Support Hong Kong Violence Act” as it has overtly taken sides with rioters who are destroying the rule of law in Hong Kong,” it continued.
Republican Senator Marco Rubio was the main sponsor of the Senate bill, which was co-sponsored by Republican Senator Jim Risch and Democratic Senators Bob Menendez and Ben Cardin.
The House passed by 417 to 0 a second bill, which the Senate also approved unanimously on Tuesday, to ban the export of certain crowd-control munitions to Hong Kong police forces. That measure bans the export of items such as tear gas, pepper spray, rubber bullets and stun guns.
President Trump has 10 days, excluding Sundays, to sign a bill passed by Congress, unless he opts to use his veto.
A person familiar with the matter told Reuters the president intended to sign the bills into law, not veto them.
Vetoes would have been difficult to sustain since the measures passed both the Republican-controlled Senate and Democratic-controlled House with almost no objections.
A two-thirds majority would be required in both the Senate and House to override a veto.
The Hong Kong government said on Thursday the passage of the bill sent the ‘wrong message’ to the protesters, Clarke said.
“The reponse from the Hong Kong government and, no doubt, China, is an angry one, telling the US to keep out of its affairs,” she said.
China issued its own condemnation of the legislation after the Senate backed the bill, and promised strong countermeasures to safeguard its sovereignty and security.
China’s foreign ministry said this month that China had lodged “stern representations” with the US about the legislation and urged that it not be passed into law, saying it would not only harm Chinese interests and China-US relations, but also the US’s own interests.
It said China would “inevitably take vigorous measures to firmly respond, to staunchly safeguard our sovereignty, security and development interests”.
Trump prompted questions about his commitment to protecting freedoms in Hong Kong when he referred in August to its mass street protests as “riots” that were a matter for China to deal with.
Trump has since called on China to handle the issue humanely, while warning that if anything bad happened in Hong Kong, it could be bad for talks to end a trade war between the world’s two largest economies.