Available 
Available 
SAN DIEGO, San Diego County, Calif., Oct. 21, 2026 — A multi-vehicle crash involving a semi-truck shut down lanes in both directions of I-5 near Old Town on Tuesday morning, October 20, according to the California Highway Patrol. The crash caused major injuries and prompted a SigAlert as crews worked to clear wreckage and a fuel spill through the afternoon.
The California Highway Patrol said the crash was first reported around 9:44 a.m. and involved a semi-truck and at least one passenger vehicle, with a white box truck and a gray sedan among the vehicles described in early radio traffic. A big rig reportedly ended up hanging over the center divider, and the truck's driver was found lying in a traffic lane. The truck also caught fire, and the driver was reported out of the vehicle before crews arrived.
What began as a report of an ambulance needed for injuries was upgraded by early afternoon to a major-injury collision involving two vehicles. The extent of injuries has not been released. No additional details on the people involved, including names or ages, have been made public.
Caltrans crews closed multiple lanes in both the northbound and southbound directions for several hours to allow fire crews to fight the truck fire, inspect a damaged roadside barrier, and manage a diesel and oil spill that investigators said covered part of the roadway. A CHP SigAlert was issued for northbound I-5 as backups built through the morning and into the afternoon. Caltrans also said a section of punctured guardrail, built to the same standard as bridge railing, would need repair, though the agency noted the damaged section is not part of a bridge structure.
By early afternoon, environmental cleanup crews began work on the southbound side of the freeway, with the responsible party for cleanup identified by Caltrans liaison staff. The crash remains under investigation.
Our thoughts are with those who were injured, and we wish them a full recovery.
More on Crashes in San Diego, CA
The truck crash was reported on I-5 in San Diego. Local crash statistics, the steps for getting a police report, and nearby trauma centers are on our San Diego crash data and police report guide.
Frequently Asked Questions
Does driver fatigue play a role in truck crashes?
It can. Commercial drivers often travel long hours, and fatigue slows reaction time much like alcohol does. Federal rules limit driving hours for this reason, but fatigue remains a factor investigators look at in many truck crashes.
What should I do if I'm in a crash involving a commercial truck?
Call 911, move to a safe spot if possible, and get medical care even if injuries seem minor. Take photos of the scene, obtain the truck company's and license information, and file a report with the responding agency.
Why do big rigs need so much distance to stop?
A loaded semi-truck can weigh twenty times as much as a passenger car. That extra weight requires far more distance and time to slow down or stop, especially at highway speeds.
What makes truck crashes different from typical car crashes?
The size and weight gap between a truck and a passenger vehicle means the smaller vehicle absorbs most of the impact. That gap tends to produce more severe injuries than crashes between two passenger cars.
What to Do After a Truck Crash in San Diego, CA
If you're involved in a truck crash in San Diego, stay as calm as possible and check yourself and any passengers for injuries before moving. Call 911 right away so paramedics and law enforcement can respond, and avoid standing in open traffic lanes while you wait. Once you're safe, document what you can: photos of vehicle positions, road conditions, and any visible damage. See a doctor promptly even if you feel fine, since some injuries from truck crashes don't show symptoms right away. Keep copies of any medical records, police reports, and insurance correspondence in case you need them later.
