SAN ANTONIO • Desperate families of migrants from Mexico and Central America frantically sought word of their loved ones as authorities began the grim task Tuesday of identifying 51 people who died after being abandoned in a tractor-trailer without air conditioning in the sweltering Texas heat.

It was the deadliest tragedy to claim the lives of migrants smuggled across the border from Mexico.

The driver of the truck and two other people were arrested, U.S. Rep. Henry Cuellar of Texas said.

He said the truck had passed through a Border Patrol checkpoint northeast of Laredo, Texas, on Interstate 35. He did not know if migrants were inside the truck when it cleared the checkpoint.

Investigators traced the truck’s registration to a residence in San Antonio and detained two men from Mexico for possession of weapons, according to criminal complaints filed by the U.S. attorney’s office. The complaints did not make specific allegations related to the deaths.

The bodies were discovered Monday afternoon on the outskirts of San Antonio when a city worker heard a cry for help from the truck parked on a lonely back road and found the gruesome scene inside, Police Chief William McManus said. Hours later, body bags lay spread on the ground.

Police check the scene Monday where dozens of people were found dead in a semitrailer in a remote area in southwestern San Antonio.

the associated press