Photo courtesy Caltrans.

A big rig jacknifed on the transition road from the northbound 710 Freeway to the eastbound 60 Freeway this morning and a portion of the trailer and cab were hanging off the bridge.

The crash was reported about 4:05 a.m., but it was unclear what caused the crash, according to the California Highway Patrol.

The driver was not injured, NBC4 reported.

The semi weighed approximately 30,000 pounds and Los Angeles County fire crews were called in for a hazmat response, the CHP said.

A SigAlert was issued for the northbound 710 Freeway connector to the east- and westbound 60 Freeway until further notice.