Joaquin Phoenix's car overturned on a canyon road and collided with another vehicle after his brakes went out, but there were no reports of injury, police said.
Phoenix, the 31-year-old star of the Johnny Cash biopic "Walk the Line," was driving eastbound above Sunset Strip about 2:50 p.m. when he realized his brakes were not working, said Officer Jason Lee, a police spokesman.
Phoenix lost control of his car, which overturned and hit another vehicle also headed eastbound, Lee said.
His publicist, Susan Patricola, said in a statement that Phoenix was wearing his seat belt and walked away from the scene after being helped out of his vehicle by a passer-by.
Earlier this month, Phoenix won a Golden Globe for best actor in a musical or comedy for portraying country legend Cash.