The UCSB Police Department received multiple reports about 3:15 p.m. Monday of a suspicious suspect at South Hall, with one caller indicating the person may have had a gun.

Officers conducted a floor-to-floor and room-to-room search, but determined that no weapon was involved. The subject was not located, and an on-site investigation revealed that the incident was possibly a prank.

The building was evacuated, then reopened about 4:20 p.m.

The university’s public alert system sent e-mails and texts to people on campus, warning, “Report of an individual possibly with a weapon although, that has not been confirmed. Police are searching the South Hall. Everyone on campus should shelter in place. South Hall occupants remain in place until evacuated by a police officer.”

UCSB Police will continue to investigate.

Noozhawk staff writer Giana Magnoli can be reached at gmagnoli@noozhawk.com.