Police in the St. Louis suburb of Berkeley say their investigation confirms an 18-year-old pointed a gun and tried to fire at the officer who shot him to death in a convenience store parking lot last week.

Police Chief Frank McCall said Tuesday that several witnesses told police Antonio Martin pointed a gun at the officer, who has not been identified. The officer was responding to a report of shoplifting at the store.

Renewed protests followed the shooting, which was the third of a black suspect by a white officer in the region since 18-year-old Michael Brown was killed by a police officer in neighboring Ferguson on Aug. 9.

McCall said a man who was with Martin at the store was among the witnesses who said Martin had a gun.