The threat was called in late Monday morning, putting all law enforcement personnel on high alert.
At 10:32 a.m. the East Baton Rouge Parish 911 center received the vague threat about three bombs on campus, LSU spokesperson Christine Calongne said.
A campus-wide evacuation was then put into effect so officials could search dorms and over 200 buildings.
By about 4:45 p.m., LSU Police Capt. Cory LaLonde said no bombs were found and that the campus would eventually reopen, but it was unclear when that would be.
Meanwhile, traffic on I-10, I-12 and all roads leading away from LSU were jammed with students, teachers, faculty and university staffers trying to get home or away from Tigertown as fast as possible.
"I've been sitting in traffic for the last three hours trying to get home," said an LSU Administrative Coordinator communicating via e-mail. "Can you imagine the hysterics of evacuating 30,000 people at the same time? We were told to leave campus immediately, but traffic was at a complete stand still for hours. I left my desk at 10:30 a.m. this morning and just arrived home a little after 3 p.m."
By 8 p.m., the LSU campus seemed to have return to normal and students were allowed back in, according to LSU's Twitter feed.
"Notifications on other campus facilities will be made as appropriate," the university's message said. "Keep your travels on campus restricted to (reopened) facilities until further notice."
Classes and events on LSU campus will be take place as originally scheduled for Tuesday, Sept. 18.
Louisiana State Police SWAT teams were sent to assist with the evacuation and used their bomb sniffing dogs.
Col. Mike Edmonston said a K-12 school that has over 1,000 students was itself evacuated in "about 45 minutes...a coordinated effort that was phenomenal."
Three other universities were also issued campus-wide alerts last week - North Dakota State, University of Texas - Austin and Hiram College in Ohio - but those turned out to be nothing more than threats and were unfounded.
Federal investigators are looking into possible links between the universities and the threats.