DALY CITY, Calif. (AP) — A police officer in the San Francisco Bay Area fatally shot a man last week during a routine check on an occupied parked vehicle after officers saw what they believed was a firearm on the lap of a passenger.

San Mateo County District Attorney Stephen Wagstaffe told The San Francisco Chronicle on Tuesday the weapon turned out to be a BB gun.

Wagstaffe said that after officers saw what appeared to be a handgun on the lap of 44-year-old Roger Cornelius, he leaned in and tried to grab it and a struggle ensued. He says another officer fatally shot Cornelius because he feared for his fellow officer's life.