Two vehicles flipped over on the 405 Freeway in Los Angeles during Thursday’s morning commute, forcing multiple northbound lanes to shut down and creating a sizable traffic jam.
The collision was reported just before 7:30 a.m. near Santa Monica Boulevard, the California Highway Patrol said.
CHP reported that at least one person connected to the crash declined transportation to a hospital. Officials did not immediately confirm whether anyone sustained serious injuries.
The overturned vehicles blocked lanes while emergency responders worked at the scene. KTLA video showed traffic backing up heavily behind the wreck, with some motorists stuck in the slowdown trying to leave the freeway.
Emergency crews respond after two cars overturned on the 405 Freeway near Santa Monica Boulevard in Los Angeles on Aug. 13, 2026. (KTLA)
A SigAlert was issued by CHP shortly after 8 a.m. for the closure of northbound lanes 4, 5 and 6 as crews moved to remove the damaged vehicles and reopen the roadway.
SigAlerts are used by CHP for unexpected incidents likely to delay a significant number of drivers for 30 minutes or longer. Crashes, spilled cargo, flooding and sudden heavy congestion can all prompt such an alert.
Around 8:30 a.m., CHP extended the SigAlert for an additional 30 minutes as the cleanup effort continued.
The collision occurred on northbound I-405 near Santa Monica Boulevard in West Los Angeles. The freeway continues north from the Westwood area toward the Sepulveda Pass.
Emergency crews respond after two cars overturned on the 405 Freeway in Los Angeles on Aug. 13, 2026. (KTLA)
Caltrans has previously directed motorists seeking an alternate northbound route from Santa Monica Boulevard to travel east to Sepulveda Boulevard before continuing north to an I-405 entrance at Moraga Drive.
The lanes affected by Thursday morning’s crash were eventually cleared and reopened.
The cause of the crash was not immediately clear, and authorities had not announced whether any citations or arrests resulted from the collision.
Traffic backs up on the 405 Freeway after two cars overturned during the Thursday morning commute in Los Angeles. (KTLA)
News Outlet reached out to the California Highway Patrol for additional information but did not immediately receive a response.

