Orange County doctor dies after being hit by automobile, beaten by driver while riding.

A Laguna Beach doctor died after being hit by a vehicle while riding a bicycle and then assaulted with a knife by the driver in Dana Point, the Orange County Sheriff’s Department said.

The attack occurred about 3 p.m. Wednesday at Pacific Coast Highway and Crown Valley Parkway, the department said in a news release.

Police arrived at the scene to find 58-year-old Michael John Mammone suffering from severe injuries. He was taken to a hospital, where he died.

Mammone had been riding his bicycle north on Pacific Coast Highway when he was hit from behind by a driver, according to authorities.

The driver, 39-year-old Long Beach resident Vanroy Evan Smith, got out of the car and assaulted Mammone with a knife, police said.

Smith was detained by bystanders and taken into custody by police. He was booked into Orange County Jail on suspicion of murder. A knife, believed to have been used in the assault, was found at the scene.

There is no known connection between the two men, and investigators are determining what led to the assault. Anyone with more information is asked to contact the Sheriff’s Department at (714) 288-6740.