SEATTLE -- A bank robber who was fatally shot by sheriff's deputies in Shoreline on Thursday was holding a fake gun, the sheriff's office said.

The gun, an Airsoft Model G26X, was a "very realistic" replica of a G-26 Block pistol. The Glock is carried by Sgt. John Urquhart, the King County Sheriff's Department.

The orange marking used on replica guns was taken off or removed, the sheriff's office said, and detectives and officers didn't realize the gun was a replica until it was picked up as evidence several hours after the shooting.

The FBI said 47-year-old James Bartlow was arrested in connection with Thursday's robbery at an Alaska USA Credit Union in a grocery store.

The King County Medical Examiner’s Office will conduct an autopsy on the suspect Friday, and release his name after next-of-kin are notified, the sheriff's office said.

Sheriff's detectives and the FBI believe the pair is responsible for several bank robberies in the Seattle, Kirkland and Shoreline areas over the past few weeks.