Authorities at Vandenberg Air Force Base say a mixup during a drill is responsible for reports of a gunman that locked down the base for several hours.

Col. Richard Boltz says the Central California facility was having a military drill Tuesday when someone blew a whistle. That's the signal used during a drill to indicate a gunshot from an armed man.

Boltz tells the Santa Barbara News-Press there was confusion about whether it was a real emergency because a gunman scenario was not part of the drill. Officials later learned someone who wasn't part of the drill blew a whistle to get someone's attention.

The base reacted to the signal as it would to a gunshot. A 911 call sent Lompoc police, sheriff's SWAT teams and crisis negotiators to the base, and the facility was sealed for two hours.


Information from: Santa Barbara News-Press, http://www.newspress.com