LA JOYA, Texas – A Texas state trooper who fired on a pickup truck from a helicopter and killed two illegal immigrants during a chase through the desert was trying to disable the vehicle and suspected it was being used to smuggle drugs, authorities said Friday.

The disclosure came a day after the incident that left two Guatemalan nationals dead on an isolated gravel road near the town of La Joya, just north of the Mexico border.

State game wardens were the first to encounter the truck Thursday. After the driver refused to stop, they radioed for help and state police responded, according to Parks and Wildlife Department spokesman Mike Cox.

When the helicopter with a sharpshooter arrived, officers concluded that the truck appeared to be carrying a “typical covered drug load” on its bed and was traveling at reckless speeds, police said.

After the shots were fired and the truck’s tires blown out, the driver lost control and crashed into a ditch. State police said a preliminary investigation revealed that the shots fired from the helicopter struck the vehicle’s occupants.

Eight people who were in the truck were arrested. At least seven were also from Guatemala. No drugs were found.

The Guatemalan consul in McAllen, Alba Caceres, told The Associated Press that the surviving witnesses told her “one died immediately, the other was apparently taken to a hospital and died on the way.”

The sharpshooter was placed on administrative leave, a standard procedure.

An expert on police chases called the decision to fire on the truck “a reckless act.”

“In 25 years following police pursuits, I hadn’t seen a situation where an officer shot a speeding vehicle from a helicopter,” said Geoffrey Alpert, professor of criminology at the University of South Carolina. Such action would be reasonable only if “you know for sure the person driving the car deserves to die and that there are no other occupants.”