The FBI has released the tape recording of the phone call that was a bogus bomb threat against the UCSD campus.

An apparently bogus bomb threat, coupled with the subsequent discovery Wednesday of a suspicious object in a medical building at the UCSD campus, prompted the evacuation of several hundred students and faculty.

A telephone caller, reportedly of the Animal Liberation Front, issued the menacing message in the mid-morning, targeting the Leichtag Family Foundation Biomedical Research Building, university officials reported.

About 10:30 a.m., a suspicious-looking device was found on the first floor of the structure, according to the San Diego Fire-Rescue Department. Authorities declined to provide a description of the object.

Police cleared everyone out of the building and seven others in the immediate area and called in a bomb squad, SDFRD information officer Maurice Luque said.

About 300 people were evacuated, a UCSD spokeswoman said.

Authorities also shut down a stretch of Gilman Drive, part of which extends onto the campus from the neighborhood to the south.

The explosives team had to clear areas surrounding the spot where the possible bomb was found before approaching the object itself, Luque said.

In the late afternoon, the personnel determined via X-ray that the device was harmless. They then began sweeping the other floor floors of the building for any other potentially hazardous items or materials, Luque said.

The FBI also was taking part in the investigation, he said.