A wildfire north of Lake Hughes Road in Castaic on Tuesday evening prompted closure of three southbound lanes of the 5 Freeway at Templin Highway, officials said.
California Highway Patrol logs showed a fourth lane remained open as of around 9 p.m.
The fire had grown to six acres by 9:10 p.m., according to the Los Angeles County Fire Department.
The fire was reported around 7:40 p.m. Information on what caused it was not immediately available.
There were no reported injuries and no property damage or evacuations.