Authorities say a shooting at a Southern California cemetery has left three people dead.

Ontario police Sgt. Jeff Higbee says detectives are investigating a possible murder-suicide after finding three people with gunshot wounds at Bellevue Memorial Park on Saturday.

He said the deceased knew each other.

A man who lives near the cemetery told the Ontario Daily Bulletin (http://bit.ly/1OrNPGq) he heard 20 shots before police arrived to the scene.