Thirteen people who died after a semitruck slammed into their packed SUV near the U.S.-Mexico border were among 44 who entered the United States through a 10-foot hole cut into Southern California's border fence, Customs and Border Protection said Wednesday.
"All are suspected to have entered the U.S. illegally," the agency said in a statement. "Border Patrol is investigating the smuggling events."
Two cars were seen on surveillance video leaving the area of the fence hole around 6 a.m. PT Tuesday, according to the agency.
One vehicle, a Chevrolet Suburban, carried 19 people and caught fire after entering the U.S. and traveling 30 miles to the intersection of Interstate 8 and State Route 115, the agency said. All passengers escaped the vehicle and were taken into custody by Border Patrol agents.
The cause of the fire was not immediately clear.
The other vehicle, a 1997 Ford Expedition with seats removed, was transporting 25 people when a big rig hit the SUV's side at the intersection of SR 115 and Norrish Road near Holtville, California, said Omar Watson, Highway Patrol Division chief.
The crash occurred about 10 miles north of the border, and a Mexican government official said at least 10 of the victims who died were Mexican nationals.
"At no point" did Border Patrol "attempt to stop or pursue either vehicle," the agency said. The opening in the fence was about 30 miles east of the crash in the heart of California's Imperial Valley, a major farming region. The area has long been a significant route for illegal border crossings.
"We pray for the accident victims and their families during this difficult time," Gregory Bovino, the Border Patrol's El Centro sector chief, said in a statement. "Human smugglers have proven time and again they have little regard for human life. Those who may be contemplating crossing the border illegally should pause to think of the dangers that all too often end in tragedy tragedies our Border Patrol Agents and first responders are unfortunately very familiar with."
Breaking news: At least 13 dead after truck slams into SUV carrying 25 near US-Mexico border
Here's what we know now:
What happened in the crash?
A preliminary report released Tuesday by the Highway Patrol said the SUV, driven by a 28-year-old resident of Mexico, "entered the intersection directly in front" of a Peterbilt truck. Police said it wasn't clear why the SUV entered the intersection, but the truck struck its left side, immediately killing the SUV driver.
Watson said 12 people were killed at the scene and a 13th person later died in the hospital. Several people were flung from the SUV while others managed to get out by the time police responded, Watson said. A few others had to be freed from the SUV.
"It would be premature for me to speculate or discuss what caused this collision. What we have to keep in mind is that 13 people died in this crash," Watson said Tuesday. "It's a very sad situation."
Who was killed and injured in the crash?
Police have not released the names of the victims. The ages of those in the SUV range from 15 to 53. No children were killed in the crash, police said.
The SUV's driver was from Mexicali, Mexico. Roberto Velasco, director of North American affairs for Mexico's Foreign Relations Department, confirmed that 10 of the people killed were Mexican.
The Mexican Consulate in Calexico said Wednesday that it had begun the process of notifying the families of the Mexican nationals killed in the crash, but they shared few new details about the incident.
"We know that there are families in the United States, as well as in several states in Mexico. The consulate has reached out to six families of the deceased individuals," said Mario Beltran Mainero, the press officer for the consulate. "We're working to reach all of them."
The consulate declined to say whether the 10 Mexican nationals killed, and the others who were injured, were part of a smuggling operation, deferring to U.S. officials.
Beltran Mainero said at least one of the six families they located is in San Diego; the remaining families are in Mexico. Four Mexican nationals who sustained minor injuries were released from the hospital in El Centro on Tuesday and were not in the custody of U.S. immigration or border officials, he said.
The truck driver, Joe Beltran, 68, of El Centro, was also taken to the hospital with "major injuries," the preliminary crash report said.
Why were so many people in the SUV?
U.S. Immigration and Customs Enforcement said in a statement that special agents from its Homeland Security Investigations unit in San Diego "have initiated a human smuggling investigation" but offered no further details.
A 1997 Expedition can carry a maximum payload of 2,000 pounds. If it had 25 people inside, that would easily exceed the payload limit, taxing the brakes and making it tougher to steer the vehicle, said Frank Borris, former head of the National Highway Traffic Safety Administration's Office of Defects Investigation.
"You're going to have extended stopping distances, delayed reactions to steering inputs and potential over-reaction to any type of high-speed lane change," said Borris, who now runs a safety consulting business.
SUVs of that age tend to be top-heavy even when not carrying a lot of weight, Borris said. "With all of that payload above the vehicle's center of gravity, it's going to make it even more unstable."
What is the area like?
Barely a mile from the site of the crash, a cemetery with unmarked bricks is a burial ground for migrants who died crossing the border from Mexico.
The area became a major route for illegal border crossings in the late 1990s after heightened enforcement in San Diego pushed migrants to more remote areas. Many crossed the All-American Canal, an aqueduct that runs along the border and unleashes Colorado River water to farms through a vast network of canals.
In 2001, John Hunter founded Water Station, a volunteer group that leaves jugs of water in giant plastic drums for dehydrated migrants. "I was trying to figure out how to stop the deaths," said Hunter, whose brother Duncan strongly advocated for border wall construction as a congressman.
Illegal crossings fell sharply in the mid-2000s but the area has remained a draw for migrants and was a priority for wall construction under former President Donald Trump. His administration's first wall project was in Calexico.
The area is also a large commuter stretch for thousands of farmworkers who legally cross the border each day.
Imperial Valley, which provides much of the lettuce, onions, broccoli and winter vegetables to U.S. supermarkets, is wrapping up its winter harvest. Many workers commute daily from Mexico during the harvest, taking buses and SUVs to the fields from downtown Calexico just before dawn.
United Farm Workers' spokesperson Marc Grossman said union workers had learned the people in the SUV were not farmworkers, though tragedies such as these used to be distressingly common for farmworkers. He recalled an accident in 1999 that killed 13 tomato pickers in west Fresno County after a crash impaled many on their own tools.
Contributing: Rafael Carranza, Kate Cimini, Emily LeCoz, Christal Hayes, USA TODAY; The Associated Press; Colin Atagi, Palm Desert Sun; Javier Arce, La Voz Arizona
This article originally appeared on USA TODAY: California crash, what to know: 13 dead; 25 people in Ford Expedition