The tractor-trailer crash was reported at approximately 6:40 a.m. Emergency crews shut down all westbound lanes of the 210 Freeway, letting cars pass the scene one at a time through the far left lane. Authorities began opening lanes later in the morning and all lanes have been reopened since.
Drivers were advised to take Foothill or Sunland boulevards as alternate routes to avoid the traffic backup.
The Los Angeles Fire Department reported that no one was hurt in the incident.
City News Service contributed to this report.