In a later interview, Boyd said the auto reached 100 miles per hour before the driver lost control and crashed.
"I think we need more boots on the ground, we need more patrol", Boyd said.
So begins an excruciating audio clip of children howling for their parents after being separated from them at the US-Mexico border. He adds that no children were in the truck. It was not immediately clear if they have defense attorneys.
At one point a man's voice can be heard over the cries saying: 'Well, we have an orchestra here, what's missing is a conductor'. The agent stopped one vehicle and called out a description of the other two, which prompted another agent to stop the second vehicle.
Four victims were pronounced dead on the scene and a fifth was pronounced dead after being airlifted to a hospital in San Antonio, Boyd said.
The crash happened in Dimmit County, Texas about 120 miles southwest of San Antonio. She told ProPublica the person who made the recording was a client of hers who asked to remain anonymous because that person feared retribution.
It appears the vehicle could have driven around the man if need be, and the man does not appear to say or make any type of threat toward the officer.
The sheriff said he didn't know where the immigrants were from but said most migrants who travel through the area are from Central America or Mexico. While officials believe numerous people were in the country illegally (the driver, though, is apparently a US citizen) there's nothing in any of the reporting that suggests officials suspected any of these people were risky or engaged in violent activities.More news: US withdraws from UN Human Rights Commission
The driver and passenger are USA citizens and are likely to face state and federal charges, Boyd said. He is still in the hospital.
Drivers for two of them complied, but the third, a Chevrolet Suburban sped up and tried to lose the tail.
"There was a big dust of dirt in the air and as soon as it settled I just saw all of the bodies", Flores said.
"I can say that it is very biblical to enforce the law".
"They take women against their will and they take them to rape them and kill them", she says.
Both sides of Highway 85 were closed. Vehicles were detoured to FM 468 and FM 1867.
The U.S. Border Patrol on Sunday allowed reporters to briefly visit the facility where it holds families arrested at the southern U.S. border, responding to new criticism and protests over the Trump administration's "zero tolerance" policy and resulting separation of families.
Boyd says this crash is why America needs a more secure border and why a building a wall is essential.