Fatal Rancho Cucamonga Motorcycle Accident on Interstate 10 Freeway (8/12)

Motorcyclist Killed in Rancho Cucamonga Collision on I-10

RANCHO CUCAMONGA, Calif. (August 12, 2025) — A fatal crash involving a motorcycle and a Cadillac shut down a lane of westbound Interstate 10 in Rancho Cucamonga Tuesday morning near Etiwanda Avenue.

The California Highway Patrol received reports of the August 12 collision at 6:57 a.m. near Etiwanda Avenue in San Bernardino County. According to CHP logs, the motorcycle rider was down in the No. 1 lane, and both the bike and Cadillac were blocking traffic.

Emergency crews responded quickly, but the rider was pronounced dead at the scene. Tow trucks were called to remove the involved vehicles, and a SigAlert was issued at 8:12 a.m., closing the No. 1 lane for about an hour during the investigation.

Authorities have not released the identity of the motorcyclist, and the cause of the crash remains under investigation.

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