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Monrovia, CA (August 21, 2026) – At least one person was injured in a collision involving a semi-truck and a Mercedes on Wednesday, August 19, along eastbound Interstate 210 near Mountain Avenue in Monrovia.
According to the California Highway Patrol incident log, the crash was reported at approximately 3:58 p.m. Initial reports indicated that a semi-truck collided with a gold Mercedes. Both vehicles were initially reported on the right shoulder.
Authorities later received reports that a male involved in the crash was bleeding from the head. Fire and emergency personnel were requested to respond.
Witnesses also reported that the Mercedes driver appeared to be impaired and was repeatedly getting in and out of the vehicle. At one point, the man was reportedly walking near traffic lanes, prompting concerns for his safety. CHP later reported that the crash was blocking traffic, including Lane 4.
Tow trucks were requested to remove the vehicles, and the freeway service patrol later closed its incident. The circumstances surrounding the collision remain under investigation.
We hope the injured person makes a full and speedy recovery.
What Do Investigators Review After a Semi-Truck Collision?
Crashes involving commercial trucks and passenger vehicles can require investigators to examine multiple types of evidence. Vehicle damage, roadway evidence, witness statements, and the positions of the vehicles may help establish how the collision occurred.
When impairment is suspected, investigators may conduct additional testing and review observations made by responding officers. Reports of a driver’s behavior at the scene can also become part of the overall investigation.
As authorities continue reviewing the circumstances surrounding the crash, additional information may become available.
