A State Police trooper shot and killed a 16-year-old who allegedly pointed a gun at him and brandished a knife in St. Mary’s County.  State Police Superintendent Colonel Jerry Jones says the Tuesday afternoon shooting happened outside of a home near the police barracks in Leonardtown. The teen, identified as Peyton Ham, picked up a knife and moved toward the trooper who fired additional shots.  Investigators have determined the teen had an airsoft gun that is a close representation of a real gun and a knife was recovered at the scene.  The trooper involved in the shooting has been placed on administrative leave during the investigation.