A flipped big-rig is blocking all lanes of southbound Interstate 5 near the Newhall Pass, backing up Los Angeles morning commuter traffic at least 10 miles.
All travel lanes are closed, but the California Highway Patrol is allowing one lane through on the right shoulder of the freeway in the Sylmar area near the Roxford Street exit.
CHP Officer Patrick Kimball says the big-rig reportedly hauling onions flipped on its side Tuesday at about 4 a.m. Traffic began building quickly, causing gridlock on I-5 and Interstate 14 in the Santa Clarita area some 30 miles north of downtown Los Angeles.
There's also a diesel spill. Kimball says freeway lanes will be closed until at least 6:20 a.m.
The cause of the crash hasn't been disclosed.
Copyright 2010 The Associated Press.