A 57-year-old man shot and killed his wife and two adult children before turning the gun on himself Thursday night at the family's Modesto home, authorities said.
Police said they were still trying to determine why the man, identified as Stephen Mingham, went on the shooting rampage.
They said Mingham called authorities at about 9:10 p.m. and told them that he had killed his family, according to Heather Graves, spokeswoman of the Modesto Police Department. The man then hung up and police went to the family home in the 2000 block of Sharilyn Drive.
Outside the home, police tried calling the family and used a loudspeaker. When there was no response, officers entered the home and found two men and a woman dead from gunshot wounds. A second woman was taken to an area hospital, where she later died from gunshot wounds.
Police identified the victims as Mingham; his wife Janet, 56; daughter Nicole, 34; and son Chad, 33.
Police believe he shot his family and then himself.
Anyone with details about the shooting deaths is urged to call Crime Stoppers at (209) 521-4636.