ORANGE, Calif. — 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.

“I’m so sad, and I can’t believe it,” the racing star said outside the house. “I grew up on this property my whole life.”

Robby Gordon recalled how his father, a racer known as “Baja Bob” in the motor sports community, instilled in him a love for competition and motor sports in the Orange County neighborhood, where many residents own horses and dirt riding trails line the suburban streets.

Police discovered the bodies Wednesday after receiving a 911 call from a neighbor making a welfare check at the request of relatives.