RIALTO, Calif. — Two people were killed early on Sunday after a minivan crashed into a semi-truck on Interstate 210 in Rialto, according to the California Highway Patrol, in a report by Pacific Attorney Group citing CHP.

The collision was reported at approximately 2:37 a.m. on the eastbound side of I-210 near Riverside Avenue. The minivan became lodged beneath the semi-truck's trailer, which was carrying a container, Pacific Attorney Group reported.

Source: Pacific Attorney Group / California Highway Patrol

The CHP incident log shows the big-rig driver had pulled over to the right shoulder to check his load when an unknown vehicle rear-ended the rig and became stuck under the trailer, and that there were four occupants in the smaller vehicle, including an unconscious passenger. That log is a preliminary dispatch record and can change as investigators work.

Source: California Highway Patrol incident log via CHP Fatal

OnSceneTV video from the scene reported that California Highway Patrol officers and Rialto firefighters responded to a traffic collision requiring extrication on the eastbound 210 Freeway, west of Riverside Avenue, and found a minivan wedged underneath the rear of a semi-truck trailer parked along the side of the freeway. The driver and front passenger were pronounced deceased at the scene, and two additional occupants were transported to local hospitals with injuries of unknown severity, OnSceneTV reported. KTLA also reported two dead after a car smashed into a semi on a Southern California freeway on Sunday.

Source: KTLA / OnSceneTV

All freeway lanes were temporarily stopped for approximately 45 minutes and a SigAlert was issued while emergency crews worked at the scene, OnSceneTV reported. Pacific Attorney Group reported the San Bernardino County Sheriff's Office coroner was notified and heavy-duty towing was requested to remove the vehicles and trailer.

The circumstances surrounding the collision remain under investigation, both reports said. Authorities have not released the names of the people who died in the reports reviewed for this story. I-210 is a major east-west trucking corridor through the Inland Empire, east of Los Angeles.