The California Highway Patrol said three lanes are shut down on Interstate 5 over the Grapevine.
Around 10:15 Sunday morning a gas tanker truck overturned near Cherry Canyon, blocking all lanes.
According to CHP, the driver was able to get out of the truck.
Officials say the tanker was carrying 24 tons of oil, and at one point it was seeping out on the west side of the freeway into a dirt embankment.
This is a developing story, check back for updates.