DIAMOND BAR, Calif. — Authorities have identified the woman who was killed in a multi-vehicle collision early Sunday morning on the northbound Orange (57) Freeway near Diamond Bar. The Los Angeles County Medical Examiner’s Office confirmed the victim as 35-year-old Rosa Mejia. Officials said Mejia was pronounced dead at the scene, though her city of residence has not been released.
According to the California Highway Patrol (CHP), the crash occurred around 3:15 a.m. just south of the interchange with the Pomona (60) Freeway. Investigators are still working to determine the cause of the collision and how many vehicles were involved. Preliminary reports indicate that several cars collided in the northbound lanes under unclear circumstances.
Emergency crews from the Los Angeles County Fire Department responded quickly, arriving within minutes of the first 911 call. Firefighters extricated Mejia from one of the vehicles at approximately 3:25 a.m., but despite their efforts, she was declared deceased shortly afterward. Officials said multiple lanes were blocked by wreckage, prompting CHP to issue a Sigalert around 3:40 a.m. All northbound lanes were temporarily closed before reopening about 20 minutes later.
Authorities have not confirmed whether other drivers or passengers were injured. Investigators are examining whether speed, impairment, or hazardous road conditions contributed to the fatal crash. They are also reviewing potential dashcam footage and interviewing witnesses to piece together a clearer timeline of events. CHP officials say any motorists who may have observed erratic driving or unusual vehicle movement in the area before the crash are encouraged to come forward.
The crash took place in a heavily traveled section of the freeway system connecting Los Angeles, Orange, and San Bernardino counties, an area known for its complex interchanges and steady flow of traffic, even during early morning hours. Residents and commuters expressed shock and sadness over the tragedy, sharing condolences online and urging drivers to stay alert, especially when visibility is reduced.
Friends and family of Rosa Mejia are mourning her sudden loss, remembering her as a caring and compassionate individual. Local authorities extended their sympathies to her loved ones, emphasizing that the investigation remains active. The CHP Baldwin Park Office continues to gather evidence and is asking anyone with information to contact investigators as they work to determine what caused the deadly collision.