A 35-year-old man is accused of opening fire on an ambulance crew around 3:45 p.m. Sunday, Tucson police Chief Chris Magnus told news outlets. The driver of the ambulance, a 20-year-old man, was shot in the head, and a paramedic in the passengers seat, a 21-year-old woman, was shot in the chest and arm. The man was in critical condition and the woman was stable.