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Irwindale, CA (June 22, 2026) – A chain-reaction traffic accident involving a big rig and multiple vehicles left one woman dead and more than 30 people hurt on Saturday morning, June 20, on the 210 Freeway in Irwindale.
The roadway disruption happened shortly before 9 a.m. just west of Irwindale Avenue. Early reports stated that an eastbound semitruck lost control, crossed the center median, and entered the westbound lanes before striking a vehicle traveling in the opposite direction. The truck jackknifed as it crossed the divider, leading to a multi-vehicle collision that blocked traffic in both directions.
A woman died at the scene. Her identity had not been released as of this report. Emergency units said 10 people were taken to nearby hospitals, including two people listed in critical condition and eight with minor injuries. Six of those receiving treatment were children.
Another 22 people reported minor harm but declined further medical care. Westbound lanes were completely shut down while three eastbound lanes were blocked, creating significant delays along the freeway corridor. Investigators continue working to determine what led the truck to cross into opposing traffic.
We extend our deepest sympathies to the loved ones of the woman who lost her life.
What Happens When a Large Truck Crosses a Highway Median?
When a large commercial truck crosses a highway median, the results can be severe because of the vehicle’s size, weight, and momentum. Median barriers are designed to reduce crossover traffic, but high-speed or out-of-control trucks can sometimes breach those protections and enter opposing lanes.
After a major roadway collision involving a truck, investigators usually review vehicle maintenance records, driver activity, roadway design, weather conditions, and any available video footage. Data from onboard electronic systems may also provide information about speed, braking, and vehicle movement before contact occurred.
Medical reports, vehicle damage patterns, and witness accounts can further help explain how the sequence of events unfolded. In crashes involving numerous vehicles, investigators may spend considerable time reconstructing traffic movements to better understand the factors that contributed to the chain reaction.
