Sig Alert, I-15, Cajon Pass 4:46 a.m.

A truck pulling a trailer collided with two other vehicles and overturned on the southbound 15 south of Oak Hill Road, blocking three lanes. The CHP reopened two lanes at 5:24 a.m., but the slow lane and right shoulder remained closed. The Sig Alert was expected to remain in effect until at least 7 a.m. The crash backed up several miles to at least Bear Valley Road in Victorville.