Tiger Woods was seriously injured when the vehicle he was driving left the road and rolled down a hillside in Southern California on Tuesday morning, authorities said.

Woods underwent surgery to repair "significant orthopaedic injuries" to his lower right leg and ankle, which included the insertion of a rod into his tibia and the use of "a combination of screws and pins" to stabilize his foot and ankle, Harbor-UCLA Medical Center chief medical officer Anish Mahajan said in a statement released on the golfer's Twitter account late Tuesday.

"He is currently awake, responsive, and recovering in his hospital room," the Twitter statement read.

Woods, 45, was the sole occupant of a gray Genesis sport utility vehicle when it crashed shortly after 7 am near the suburban communities of Rolling Hills Estates and Rancho Palos Verdes, 23 miles south of downtown Los Angeles, the Los Angeles County Sheriff's Department said in a statement.

Sheriff's Deputy Joana Warren told Reuters the vehicle had gone off the highway and rolled down the hillside before coming to rest at the bottom.

Sources said Woods, who was conscious when first responders arrived, had to be removed through the car's windshield, the Los Angeles Times reported.

"Because of the situation and the way that you found the vehicle, he wasn't able to open the door and come out," LA County Fire Department spokesman Henry Narvaez said.

County Sheriff Alex Villanueva said Woods is "lucky to be alive".

The airbags deployed, and the inside of the car stayed mostly intact, which "gave him a cushion to survive the crash", Villanueva said.