The father of former NASCAR driver Robby Gordon strangled his wife then shot himself in their Southern California home, police said Thursday.

The deaths of Robert Gordon, 68, and Sharon Gordon, 57, were an apparent murder-suicide, Orange police Lt. Fred Lopez said a day after the bodies were found. No further details on the motive or circumstances were released.

The couple were the father and stepmother of ex-NASCAR star Robby Gordon, who fought back tears and expressed disbelief Thursday outside the home on a Southern California hillside where he grew up and developed his love of racing.