This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated.

(KTLA) – Investigators in California are still trying to determine why a driver struck a bicyclist with his car and then stabbed him to death in Orange County on Wednesday.

The victim has been identified as Michael Mammone, 58, an emergency room doctor at Providence Mission Hospital in Laguna Beach.

Authorities say Vanroy Smith, 39, of Long Beach, struck Mammone with his white Lexus sedan at an intersection in Dana Point around 3 p.m. Wednesday.

Michael Mammone
Michael Mammone is seen in a photo released by Providence Mission Hospital on Feb. 2, 2023.

Witnesses told deputies that after the collision, Smith got out of his vehicle and assaulted Mammone, stabbing him several times.

Smith was detained by witnesses at the scene until law enforcement arrived, authorities said.

Mammone died at a hospital.

Investigators have not yet found any connection between the two men.

“As of right now we currently don’t truly understand the why… as far as motivation and any type of relationship,” Orange County Sheriff’s Sgt. Mike Woodruff told Nexstar’s KTLA. “Investigators are keeping all options open to check those boxes, if you will, to make sure they don’t leave anything uncovered.”

Dana Point Bicyclist Killed
The scene of the fatal incident is seen from above, in Dana Point, Feb. 1, 2023 (KTLA)

Providence Mission Hospital issued a statement Thursday calling Dr. Mammone’s death a “stunning tragedy.”

“The entire Mission Hospital family is grieving over the loss of an incredible physician and friend,” the statement read. “We will honor Dr. Mammone’s dedication to our community and passion for medicine by continuing to provide exceptional care.”

Smith has been booked on suspicion of murder.