A crash involving at least five vehicles has caused a miles-long backup on the southbound 405 Freeway in the Van Nuys area Tuesday morning.
The incident happened near Victory Boulevard at around 5:30 a.m., according to the California Highway Patrol's incident log.
It was not immediately clear whether anyone was injured.
All but two lanes were inaccessible to motorists as officials responded to the scene, where vehicles that were apparently involved in a chain-reaction crash came to a rest across several lanes.
Traffic was backed up to the 118 Freeway.
CHP did not give an estimate on when all lanes of the freeway would reopen.
Authorities provided no further details.