RICHMOND -- Officers who shot a man Monday evening behind a Richmond apartment building fired their weapons after the suspect first pointed his gun at police as they approached, police said Thursday.

The 30-year-old man, later identified as Elston Young, of San Francisco, was critically injured after being shot multiple times in the torso, Richmond police Lt. Bisa French said. He was upgraded to stable condition after undergoing emergency surgery Monday evening.

Officers confronted Young on the sidewalk at 4:57 p.m. behind St. Johns Apartments at Nevin Avenue and B Street, after several 911 callers reported seeing an armed man in the area and police ShotSpotter technology detected shots at the location.

Police did not address what Young did to prompt lethal force, but released new information Thursday suggesting that he pointed his gun at the arriving officers.

According to French, the ShotSpotter detection, along with rounds collected at the scene, suggest that Young fired his gun before police arrived. Forensic analysis is being performed on additional casings found at the scene to determine whether he fired back -- officers at the scene were not certain whether he fired at them during the incident, she said.

No other injuries were reported in the incident, French said.

Authorities were still piecing together what Young was doing in the area with the gun, but said he knows someone in the neighborhood, French said. Residents in the area declined to comment on the shooting Tuesday.

French said the District Attorney's Office planned to file a charge of assault with a deadly weapon against Young, but those proceedings will be delayed until next week in light of a separate officer-involved shooting in Pittsburg on Tuesday.

The officers involved in the Richmond shooting have been placed on paid administrative leave. The incident was the first officer-involved shooting in Richmond since December 2011, when police shot and wounded a man after a witness reported him carrying a gun at a hotel near Hilltop Mall.

Staff writer Robert Rogers contributed to this report.