Northbound lanes on the San Diego (405) Freeway near Sepulveda Boulevard in Sherman Oaks slowly reopened Thursday night after a tractor-trailer jackknifed and spilled gallons of diesel onto the roadway, California Highway Patrol officials say.

As of about 8:30 p.m., only two of the freeway's six northbound lanes remained closed, according to CHP.

Traffic was flowing on the carpool and number one, two, three and four lanes. It was not immediately known how long the other lanes would remain closed.

The incident prompted a SigAlert for the traffic-prone portion of the freeway during rush hour at about 5:41 p.m..

Aerial video showed the truck pulled over with fuel spilled across the roadway.

At least one person was transported to the hospital after the big rig and at least two other vehicles collided during the rush hour commute, according to Erik Scott with LAFD.

The semi was blocking only the right lane, but fire trucks prevented vehicles from crossing over the spilled fuel.

Traffic continued on Thursday night to be backed up for miles coming down from the Sepulveda Pass (map). Southbound lanes are slow in pockets from Sunset to Bellflower boulevards, according to SigAlert.

Motorists can use Sepulveda Boulevard as an alternate route.

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