SAN DIEGO — An overturned big rig is blocking several lanes of northbound Interstate 15 Tuesday near Mission Valley, Caltrans said in a tweet.

The incident was first reported around 12:30 p.m. on northbound I-15 just south of Interstate 8, according to the California Highway Patrol Traffic Incident Information page.

The three left-hand lanes of northbound I-15 are blocked due to the overturned truck.

It is not yet known if anyone was injured in the crash.

The vehicle, which partially landed on Camino Del Rio, was carrying between 20,000 and 30,000 pounds of dirt, CHP logs indicated.

Officials did not indicate when the freeway lanes could be reopened.