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PASADENA, Los Angeles County, CA, Sept. 23, 2026 — A multi-vehicle crash with injuries shut down lanes on westbound Interstate 210 near N Allen Ave Tuesday evening, September 22, according to the California Highway Patrol.
The crash reportedly involved four vehicles, including two Toyotas, and left debris in the number 2 lane, the CHP incident log shows. A sedan, a red vehicle and at least one other unidentified vehicle were reportedly involved, authorities said. The collision blocked a slow lane on the westbound side near the N Allen Ave interchange.
Pasadena Fire Department personnel responded to the scene, according to the CHP log. Caltrans freeway service patrol crews later moved the involved vehicles to the right shoulder so crews could continue clearing the scene, the log indicates. One of the Toyotas was reported disabled on the shoulder following the crash.
Two vehicles were towed from the scene by a rotation tow company, CHP records show. The extent of any injuries has not been released. The crash remains under investigation, and no cause has been confirmed.
We wish the injured a complete and speedy recovery.
When Multi-Vehicle Pileups Are Most Likely on Freeways Like I-210
Chain-reaction crashes on urban freeways tend to cluster around the evening commute, when traffic volume peaks and following distances shrink as lanes fill. Dusk and early nightfall in this stretch of the year are another factor: headlight glare and dimming light make it harder for drivers to judge closing speeds on vehicles ahead.
Weekday evenings also mix commuters, delivery vehicles and long-haul traffic merging near interchanges, which is where sudden slowdowns begin. A single hard brake near an on-ramp can ripple backward through several lanes before drivers further back have time to react.
According to the National Highway Traffic Safety Administration, 2,979 passenger-car occupants were killed in two-vehicle crashes involving a passenger car and a light truck in 2023. That difference in vehicle size and weight is a factor when multiple vehicles are involved in a single chain-reaction crash.
Frequently Asked Questions
Why are multi-vehicle crashes harder to investigate than two-car collisions?
Investigators have to reconstruct the sequence of impacts, determine which vehicle struck which, and separate what happened from what witnesses believed they saw. Physical evidence like debris fields and paint transfer is more important than driver accounts.
What typically causes a chain-reaction pileup?
An initial slowdown or crash, normally paired with following distances that don't leave following drivers room to stop. Reduced visibility, distraction and speed differences between vehicles all raise the odds that a stop turns into a series of impacts.
How can drivers avoid getting caught in one?
Leaving extra space behind the vehicle ahead and watching brake lights several cars up, not just the car directly in front, gives more time to react if traffic suddenly stops.
What to Do After a Multi-Vehicle Crash in Pasadena, CA
If you're involved in a multi-vehicle crash, try to move to the shoulder or a safe area if your vehicle is drivable and it's safe to do so. Turn on hazard lights and check on passengers and nearby drivers before stepping out into traffic lanes.
Even if injuries seem minor, a medical check is worth doing soon after, since some injuries from being jolted or thrown against a seatbelt or airbag don't show symptoms right away. Get contact information from other drivers and note any responding agencies, since multiple departments may be involved in a crash this size.
File or follow up on the official crash report once it's available. With several vehicles involved, having documentation matters more than in a simple two-car crash.
