The Tucson Police Department says one of its guns is missing.

Police say an officer who helped locate a purse-snatching and shoplifting suspect following a foot chase on the city's west side Monday discovered that his service weapon had been dislodged from his holster.

Officers retraced the path of the foot chase but couldn't locate the weapon, and further searching didn't turn it up either.

The gun is a Glock with an attached tactical light.

The suspect was taken into custody in the vicinity of the 500 block of North Shawnee Avenue.

Police are asking anyone with information to call 911.