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SAN LORENZO, Alameda County, Calif., Sept. 29, 2026 — Four vehicles collided Monday evening, September 28, on Via Toledo in San Lorenzo, according to the California Highway Patrol. At least one person suffered minor injuries, the agency reported.
The crash happened in the 15900 block of Via Toledo shortly before 6 p.m. Dispatch logs show the collision was first classified as a two-vehicle crash with no injuries before it was updated to reflect four vehicles involved and at least one minor injury.
An ambulance was requested for a possible injury early in the response, and a tow was later called to the scene to clear a Honda Civic, according to the CHP log. Officers had all involved vehicles blocking traffic for a period while units worked to clear the roadway, the agency reported.
Eastbound lanes near Paseo Grande were affected as crews managed traffic around the wreck. The agency closed out its incident by around 6:07 p.m. Monday.
The California Highway Patrol's investigation into the collision remains open. Our thoughts are with those who were injured, and we wish them a full recovery.
How Investigators Piece Together a Multi-Vehicle Crash
When several vehicles collide in a short stretch of road, reconstructing what happened takes more than a quick look at the wreckage. Officers typically document the position of each vehicle, skid marks, debris fields, and damage patterns before anything is moved, since that evidence can be lost once traffic starts flowing again. Witness statements are gathered at the scene, but many are followed up later once people have had time to recall details clearly.
Investigators often need to determine the order in which vehicles struck each other, which is harder than it sounds when four vehicles are involved. That can mean pulling data from onboard systems, reviewing any available video, and cross-checking accounts from multiple drivers and passengers. This process can take days or weeks, particularly if injuries or conflicting statements complicate the sequence of events.
According to the National Highway Traffic Safety Administration, 28,595 large-truck occupants were injured in multi-vehicle crashes involving large trucks in 2023. That figure reflects how often crashes involving more than two vehicles produce injuries, and why agencies take time to get the full picture right before closing a case or releasing a final report.
Frequently Asked Questions
Why do chain-reaction crashes happen?
They often start with one vehicle slowing, stopping, or losing control, and other drivers following too closely or reacting late get pulled into the collision. Traffic volume, speed, and driver distraction all play a role in how many vehicles end up involved.
How can drivers avoid being caught in a pile-up?
Keeping a safe following distance and watching several car lengths ahead, not just the vehicle directly in front, gives drivers more time to react if traffic suddenly slows or a crash occurs nearby.
What should I do if I'm stopped near a crash on the highway?
Turn on hazard lights, stay in the vehicle if it's safe to do so, and move as far from moving traffic as possible. Getting out to inspect damage or exchange information in an active lane adds risk.
How does fog or low visibility contribute to pile-ups?
Reduced visibility shortens the time drivers have to see and react to slowed or stopped traffic ahead, which is why multi-vehicle crashes tend to cluster in fog, heavy rain, or smoke conditions.
What to Do After a Multi-Vehicle Crash in San Lorenzo, CA
If you're involved in a crash with several other vehicles, start by checking yourself and any passengers for injuries before moving, if it's safe to stay put. Call 911 to report the collision and request medical help if anyone is hurt, even if injuries seem minor at first.
Move to a safe location away from traffic if you're able to, and exchange information with other drivers once it's safe to do so. Getting checked by a medical professional afterward matters even without visible injuries, since some symptoms take hours or days to appear. Keep a copy of the CHP incident report for your records and follow up with the agency if you have questions about the investigation's progress.
