Identities of the other two victims are being withheld pending family notifications. They are a 28-year-old from Chicago and a 38-year-old from San Antonio.
Officer JoAnn Taylor says detectives are trying to interview neighbors and potential witnesses to determine a suspect and motives.
The three were found shot multiple times when the garage owner came home shortly after one a-m this morning. Two were inside a Ford Windstar minivan and the other was on the garage floor near a Volkswagen beetle.
Taylor says police found a semiautomatic handgun by one of the victims.