SAN ANTONIO (AP) — A Texas truck driver charged in the deaths of 53 migrants who rode in a sweltering tractor-trailer with no air conditioning pleaded guilty Thursday over the 2022 tragedy that became the nation’s deadliest smuggling attempt across the U.S.-Mexico border.

Homero Zamorano Jr., who lived in Texas, pleaded guilty to three charges and could face a maximum sentence of life in prison, the Justice Department announced.

Authorities say Zamorano, who drove the truck, and other men charged in the smuggling attempt were aware that the trailer’s air-conditioning unit was malfunctioning and would not blow cool air to the migrants trapped inside during the sweltering, three-hour ride from the border city of Laredo to San Antonio.

Temperatures reached 100 degrees Fahrenheit (38 Celsius) while migrants screamed and banged the walls of the trailer for help or tried to claw their way out, investigators said.

The truck had been packed with 67 people, and the dead included 27 from Mexico, 14 from Honduras, seven from Guatemala and two from El Salvador, according to Mexican authorities. Prosecutors have said migrants paid up to $15,000 each to be taken across the U.S. border.

Also charged previously in the tragedy was Christian Martinez, also of Texas, who with Zamorano was arrested shortly after the migrants were found. Martinez has since pleaded guilty to smuggling-related charges.

Four Mexican nationals were also arrested in the case in 2023. And in August, a suspect arrested in Guatemala was charged with helping coordinate the smuggling attempt. U.S. authorities they would seek the extradition of Rigoberto Román Miranda Orozco, who is charged with six counts of migrant smuggling resulting in death or serious injury. Authorities alleged he is connected to four Guatemalan migrants in the trailer, three of whom died, and faces up to life in prison if convicted.