Louisiana State University said late Monday that the campus had reopened after authorities spent most of the day investigating a bomb threat.
No device was found.
An anonymous call came into 911 at 10:32 a.m., university spokesperson Kristine Calongne told the Los Angeles Times. The Baton Rouge campus was evacuated about an hour later.
By evening, students were allowed to return to dorms but authorities continued to search for explosives in other campus buildings.
LSU said the entire campus was back to normal shortly before 11 p.m.
"All campus buildings have been returned to normal operations and the campus is now open for students, faculty and staff," LSU said on its website. The investigation into the threat was ongoing, LSU said. Classes were to resume Tuesday.
The bogus threat was the fourth in a week involving an American university. Others occurred at the University of Texas at Austin, North Dakota State University in Fargo and Hiram College in Ohio.