The death of a 22-year-old man who crashed his car Saturday afternoon remains shrouded in mystery. Patrick Lobor, a former Deering High School basketball player, struck a vehicle that had stopped for a red light at Brighton Avenue and Riverside Street. After the accident, police said, Lobor got out of his car, stumbled to the middle of the intersection and collapsed. An autopsy showed he died of a stab wound to the chest.