According to News 4 in San Antonio, 12 of the people inside the vehicle were ejected during the crash and four were pronounced dead at the scene.
Some of the injured passengers were flown by medical helicopters to hospitals in San Antonio, and others were taken by ambulances to a hospital in Dimmit County.
He said there were 14 people in the vehicle.
Four people were pronounced dead at the scene, others were taken to area hospitals. Officials said they believe the driver is a US citizen.
Most of the occupants were believed to be living in the country without legal permission according to Fox. He said one passenger was taken into custody.
Five undocumented immigrants in a speeding sport utility vehicle were killed Sunday when it crashed while being chased by border patrol agents and a sheriff's deputy in a Texas town about 50 miles from the border with Mexico, officials said. He said the pursuit was the result of "good police work", and gave his support for the construction of a border wall.
Border Patrol officials have repeatedly warned of the dangers of smuggling large numbers of people in vehicles. He added such chases, not the crash, happened nearly every day. "We've seen this many, many times".
Local law enforcement were familiar with the driver, who was in the area last week to either pick up undocumented immigrants or the scout, the sheriff said.
Boyd added: "If it can be built, I think it needs to be built".