In the moments before the accidental shooting of a Nassau County (N.Y.) Police officer by an MTA officer, retired NYPD Sgt. John Cafarella may have yelled "gun," triggering the shooting.
Cafarella was in the area and had stopped to offer his help. The New York Times is reporting the retired NYPD sergeant yelled "gun," after seeing Officer Geoffrey Breitkopf arrive on-scene with a rifle.








