Investigators believe excessive speed and impairment by alcohol or drugs may have played a role in a crash on the 5 freeway that killed four people Thursday, according to a report released by the California Highway Patrol.

The report cited “excessive speed” and “alcohol and/or drugs” as potential contributing factors in the collision, according to CHP.

The identities of the four people killed in the fiery crash were not disclosed by CHP officials Sunday, pending notification of their next of kin.

All four, three men and a woman, were declared dead at the scene.

See Related: UPDATE: Four Killed In Fiery Crash On Northbound I-5 In Newhall

According to the CHP report, a black van, traveling northbound on I-5 north of Weldon Canyon Road, collided with a Freightliner truck parked on the shoulder of the freeway at a high rate of speed just before 7:30 p.m.

The collision caused the van to catch fire, subsequently lighting the Freightliner’s trailer. The blaze was extinguished by firefighters with the Los Angeles County Fire Department.

According to the crash report, all four occupants of the vehicle were wearing seatbelts at the time of the crash.

CHP investigators are still working to determine the cause of the crash. Anybody who witnessed the incident is encouraged to contact the CHP Newhall office at 661-294-5540

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