(NewsNation Now) — Bomb threats prompted evacuations at multiple universities in cities on both U.S. coasts Thursday.

Three buildings at the University of Southern California (USC) in Los Angeles were evacuated Thursday afternoon due to a bomb threat, campus officials said.

USC sent out an alert to students, faculty and staff just after 3:30 p.m., saying Grace Ford Salvatori Hall, Sample Hall and Wallis Annenberg Hall were being cleared out.

The Los Angeles Police Department and the USC Department of Public Safety are conducting a search.

On the East Coast, bomb threats at New York University led to the evacuation of at least two buildings: the Stern School of Business and the Center for Neural Science, according to the university.

Police were also on the campus of the Massachusetts Institute of Technology in Cambridge on Thursday; a bomb threat there led to the evacuation of Building 54.

Last weekend, multiple unfounded bomb threats were made toward Ivy League campuses, university and law enforcement officials said.

Cornell, Columbia and Brown universities had alerted students to threats Sunday and deemed campuses safe a few hours later. Evacuations were ordered in some buildings on the campuses.

Two days earlier, a bomb threat at Yale forced the evacuation of several buildings as well as nearby businesses in New Haven, Connecticut. The university resumed normal operations Friday evening.

The Associated Press and NewsNation affiliate KTLA contributed to this report.