Authorities conducted an extensive search of the Isla Vista coastline early Saturday after receiving a report of someone in distress in the water.
Crews were called out shortly before 3 a.m. to the 6700 block of Del Playa Drive, said Santa Barbara County Fire Department spokesman Paul Christensen.
The search team included water-rescue personnel and a county helicopter.
Crews were waiting for the tide to recede to continue their search.
The incident occurred as authorities were bracing for Saturday's "Deltopia" street party in Isla Vista, which last year was marred by the death of a woman who fell from the cliffs, and a balcony collapse that sent several people to the hospital.
The county has ordered the beaches in Isla Vista and at UCSB closed for the weekend to prevent partying there.
Check back with Noozhawk for updates to this story.