A New Year's Day shooting that left four dead at a condominium near San Diego was a murder-suicide involving a 25-year-old Navy pilot who killed himself, officials said Wednesday.

Autopsy results show John Robert Reeves shot himself in the head, and the three others with him were murdered, the San Diego County Sheriff's Department said.

A fellow Navy pilot, 25-year-old David Reis, was killed by a gunshot wound to the torso and his 24-year-old sister, Karen, suffered a gunshot wound to the head and chest, officials said. A 31-year-old Chula Vista man, Matthew Saturley, was shot multiple times.

No details on the motive of the killings were released. Officials previously said that one of the men was found dead in the doorway of the three-story condo and the bodies of two men and a woman were inside the home.

The deaths shook Coronado, a picturesque peninsular enclave of 24,000 people on San Diego Bay that draws tourists and recorded only one homicide in 2010. The city is home to Naval Air Station North Island, serves as a training area for Navy SEALs, and is a haven for Navy retirees.

David Reis shared the condominium with two Navy pilots, said neighbor Don Hubbard, a retired Navy commander.

Hubbard was awakened by shots that he thought were fired by New Year's revelers. He went back to sleep, but two hours later got a phone call and heard SWAT teams swarming the area.