The California Highway Patrol said over two dozen people were in a maroon 1997 Ford Expedition, which would typically seat eight to nine people legally, that collided with an empty tractor-trailer on Highway 115 at Norrish Road in Holtville -- located about 125 miles east of San Diego and about 15 miles north of the Mexico border.
CHP officials say at the intersection the SUV drove "directly in the path of the big rig" around 6:15 a.m. The 2011 Peterbilt truck struck the left side of the SUV, which appeared to have been pushed off the road. Investigators were trying to determine if the SUV first stopped at the stop sign before entering the intersection.
Authorities said the ages of those who were inside the vehicle, including those injured and killed, ranged from 15 to 53. Numerous people were ejected onto the roadway as a result of the collision, according to officials. Initial reports said there were young children in the SUV, but officials later said the youngest occupant was 15.
The driver of the SUV, who was among those killed, was described as a man from Mexicali. Information about the occupants of the SUV, including where they were traveling to and from and why there were so many in one vehicle, is still under investigation.
The Mexican government issued a statement saying that the consulate has confirmed that at least 10 of the deceased were Mexican nationals and authorities were still working to confirm the identities of the other three who were killed in the crash.
U.S. Immigration and Customs Enforcement confirmed its agents were on scene to investigate if human smuggling was involved.
"Special Agents from Homeland Security Investigations San Diego responded to the scene of today's fatal crash in El Centro, California, and have initiated a human smuggling investigation," the agency said. "The investigation is ongoing and no further details are available at this time."
Officials said the SUV had interior seats removed, so that there were only seats for the driver and front passenger, and no seats or seat belts available for the other occupants.
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Judy Cruz, director of El Centro Regional Medical Center's emergency department, initially said 14 people died at the scene and another died after arriving. However, authorities later said 12 occupants including the driver succumbed to injuries on the scene. One other person was transported to an area hospital where they also succumbed to their injuries.
Multiple patients were sent to hospitals for their injuries, including four flown to Desert Regional Medical Center in Palm Springs, spokesman Todd Burke said. Three were in intensive care, he said. The truck driver, a 69-year-old man from El Centro, Calif., sustained moderate injuries and was transported to Desert Regional Medical Center.
Imperial County Fire officials said the crash prompted a second-alarm response, with 25 additional personnel called to the scene along with at least four additional ambulances and four air helicopters.