US President Donald Trump has threatened to cut funding to a Californian university after protesters smashed windows and set fires, forcing the cancellation of an appearance by a far-right speaker.
The violent protests broke out at the University of California at Berkeley over a scheduled speech by the editor of Breitbart News.
The campus was put on lockdown after protesters threw smoke bombs, broke windows and lit a bonfire in the university square.
They were angry over a visit to the university by Milo Yiannopoulos, who is linked to the so-called "alt-right" movement. Mr Yiannopoulous' speech was cancelled.
It was the second time in two weeks rowdy protests forced the cancellation of one of his planned addresses.
Mr Trump responded to the protests by tweeting: "If U.C. Berkeley does not allow free speech and practices violence on innocent people with a different point of view - NO FEDERAL FUNDS?"
Mr Trump's threat provoked a response from California lawmakers, who in discussions on the floor of the state senate called it distasteful and an abuse of power, marking the latest clash between the Republican president and officials in the Democratic-majority state.
It was not immediately clear what action Mr Trump could take without authorisation from Congress, or without risking legal action.
In California, a mostly Democratic state where lawmakers have already begun preparing legislation to combat Mr Trump's policies on immigration and climate change, the response was swift.
"To have the man at the helm of the most powerful nation of the world tweeting and threatening the University of California and talking about withholding funds, that's unique and I find that very distasteful," said Senate leader Kevin de Leon, a Los Angeles Democrat.
Lawmakers said they would look into whether President Trump could actually take funds from the university, which receives US$400 to US$450 million in funding for research annually. In 2016, the university also received US$216 million in federal student aid, a legislative official said.
"All we have to go on now is another angry tweet," Assembly Speaker Anthony Rendon, a Democrat from the Los Angeles suburb of Paramount, said.
He said lawmakers would continue to seek ways to protect the state, a Democratic stronghold where voters went two-to-one for Mr Trump's opponent, Hillary Clinton in the November, 2016 election.
"We have been having ongoing discussions on how to protect California from potential harm from the Trump Administration - those discussions will continue," Mr Rendon said.
Berkeley Chancellor Nicholas Dirks condemned the violence.
"Last night the Berkeley campus was invaded by more than 100 armed individuals clad in all black who utilised paramilitary tactics to engage in violent, destructive behavior," Mr Dirks said.
The 38,000-student campus, home to the Free Speech Movement of the 1960s, respected Mr Yiannopoulos' right to speak, he said.
US Representative Barbara Lee, a Democrat whose district includes Berkeley, vowed to fight any attempt to slash funding.
"Simply put, President Trump's empty threat to cut funding from UC Berkeley is an abuse of power," Ms Lee said.
According to a Reuters review, the research money received by the university includes $121 million from the National Science Foundation for scientific research and $125 million from the Health and Human Services department for health and medical research.
It may be difficult for Mr Trump to cut off this money, as much of it is awarded through a competitive process that evaluates projects based on scientific merit.
Mr Yiannopoulos has been a provocative figure on the internet for years, and has been widely criticised for comments he has made about Muslims, Black Lives Matter activists and feminists.
"Obviously it's a liberal campus so they hate any libertarians or conservatives who dare to express an opinion on their campuses," he told Fox News. "They particularly don't like me."