Sen. Bernie Sanders (I-Vt.) is accusing President Donald Trump of extorting universities and is urging these schools to protect free speech by resisting those efforts.

Sanders, ranking member of the Senate HELP committee, outlined Trump administration “attacks” on the First Amendment at colleges and universities in a 23-page minority staff report obtained by POLITICO Wednesday.

The Trump administration’s actions include withholding nearly $3 billion for higher education and launching federal civil rights probes that have resulted in cash settlements with universities that amount to extortion, according to the report.

The administration has also revoked the visas of at least 6,000 international students and issued a higher education compact with “egregious” terms that restrict free speech on campus, the report stated.

Federal courts have found the administration likely violated the First Amendment in at least 17 higher education-related cases while at least 50 university faculty and staff have resigned or have been fired for their political views, according to the report.