A speech by conservative firebrand and  Milo Yiannopoulos was canceled at UC Berkeley on Wednesday amid violent protests that prompted President Trump to suggest cutting funding to the university.

“If U.C. Berkeley does not allow free speech and practices violence on innocent people with a different point of view – NO FEDERAL FUNDS?” Trump wrote on Twitter.

It’s unclear whether Trump was actually threatening to cut funding or making some kind of rhetorical point. The larger UC system, for which Berkeley is the flagship campus, receives billions of dollars from the federal government to fund a variety of programs, notably research, student aide and health care programs.

Research is the most important area.

“Federal funds are the University’s single most important source of support for research, generating $2.8 billion and accounting for nearly 51% of all University research expenditures in 2013-14,” according to a UC report. “While UC researchers receive support from virtually all federal agencies, the National Institutes of Health and the National Science Foundation are the two largest sponsors, accounting for nearly 80% of UC’s federal research contract and grant awards.”

The UC, for example, manages the Lawrence Berkeley National Laboratory, which gets more than $700 million in federal funds, that report said.

As for federal student aid, the UC got more than $1.6 million in 2014.

University officials called off the event about two hours before Yiannopoulos was to speak at the student union, where more than 1,500 people had gathered outside. Some hurled metal barricades and others smashed windows at the student union.

“This is not a proud night for this campus, the home of the free speech movement,” said Dan Mogulof, a Berkeley spokesman. He noted that the vandalism interfered with the ability of the Berkeley College Republicans — who hosted Yiannopoulos — to exercise their 1st Amendment rights.