FAIRFIELD (CBS SF) — A lockdown at Travis Air Force Base on Wednesday afternoon, following a report of an active shooter, has been lifted.

But a California congressman told The Associate Press that a mistaken report of a shooter led to the Travis Air Force Base lockdown.

U.S. Rep. John Garamendi, who was briefed on the situation, told The Associated Press there was a training exercise underway at the base at the time and “someone took that to be an active shooter.”

At 5:05 p.m., Travis Air Force Base, located approximately 45 miles northeast of San Francisco, said via Facebook, “emergency personnel responded to reports of gun shots at the Base Exchange. However, no shooter was found. The base is no longer under lockdown.”