Chaffey College canceled classes Thursday while authorities investigated a report of a man with a possible explosive device on campus.
Deputies were searching each classroom and all cars leaving the Rancho Cucamonga campus in the 5800 block of Haven Avenue, but nothing suspicious had been found, said Cindy Bachman, spokeswoman for the San Bernardino County Sheriff's Department.
The campus was locked down before classes were canceled and no one was allowed to enter. All classes scheduled after 3:30 p.m. were canceled.
The threat was reported just after 1 p.m. when deputies received a call that an unknown man had been seen carrying a backpack with what appeared to be an explosive inside, she said.
Soon after, a large numbers of deputies responded to the campus and began searching.
The semester started Monday, so some students were weary about leaving campus for fear they could be dropped from their classes, said college spokeswoman Peggy Cartwright.
Thousands of students were on campus during the search.