Boston Police investigating the fatal shooting of a 22-year-old man late Saturday night are looking for a silver car that fled the scene on Blue Hill Avenue. The shooting occurred just before midnight, police said. Officers from the station in Mattapan responded around 11:48 p.m. and found the victim outside of 1556 Blue Hill Ave. suffering from multiple gunshot wounds. He was pronounced dead at the Boston Medical Center. As of yesterday afternoon, police had not released the victim’s identity, and no arrests had been made. The Boston Police Homicide Unit is asking anyone with knowledge of the shooting - especially about the silver car that fled the scene - to call the Homicide Unit at 617-343-4470. Information can also be reported anonymously by calling the CrimeStoppers Tip Line at 1-800-494-8477 or by texting the word “tip’’ to CRIME (27463).