The crash occurred shortly after midnight just east of the Lowell Boulevard off-ramp in the Glendale/La-Crescenta area, according to the California Highway Patrol.
All westbound lanes of the 210 were closed between Lowell and the Pennsylvania Avenue off-ramps. Two lanes reopened at about 6:20 a.m. All lanes have since reopened.
Traffic was diverted off at Pennsylvania Avenue. Commuters were advised to get back on the 210 via Foothill Boulevard, then Lowell Avenue. Eastbound traffic did not appear to be affected.
Officials say a big rig rear-ended another big rig that slowed down unexpectedly. The crash ignited a fire, burning one big rig to the ground. Authorities say both drivers were able to escape unharmed, though one driver suffered a minor injury.