ABC News June 27, 2023

4 more suspects charged in deadliest US smuggling attempt

WATCH: 4 more suspects charged in deadliest US smuggling attempt

One year after 53 people, including six kids, were killed in an abandoned sweltering tractor-trailer near San Antonio during an alleged smuggling attempt, the Justice Department announced it has indicted and arrested four men for the incident.

Riley Covarrubias-Ponce, Felipe Orduna-Torres, Luis Alberto Rivera-Leal and Armando Gonzales-Ortega were all arrested and charged on several counts including conspiracy and alien smuggling resulting in death, the Justice Department announced Tuesday.

The four men allegedly participated with three other suspects, Homero Zamorano and Christian Martinez who were previously indicted and arrested, and a seventh unidentified suspect in a human smuggling organization that attempted to bring 66 people into the United States on June 27, 2022, the indictment said.

Eric Gay/AP, FILE
In this June 27, 2022, file photo, police and other first responders work the scene where dozens of people were found dead and multiple others were taken to hospitals after a tractor-trailer containing suspected migrants was found in San Antonio.

The migrants and their families, a majority from Mexico, Guatemala and Honduras, paid between $12,000 and $15,000 each to be brought into the country, the indictment said.

MORE: 4 charged after 53 found dead in Texas tractor-trailer

The indictment detailed how the men allegedly worked together to use trucking routes, local guides, stash houses, trucks and trailers to transport the group. To make sure they properly kept track of the group, each migrant was given the code word "clave" to recite at different points in their journey, according to the indictment.

Jordan Vonderhaar/Getty Images, FILE
In this June 27, 2022, file photo, members of law enforcement investigate a tractor-trailer in San Antonio, Texas. According to reports, at least 46 people, who are believed migrant workers from Mexico, were found dead in an abandoned tractor trailer. Over a dozen victims were found alive, suffering from heat stroke and taken to local hospitals.

Prosecutors said the men knew the tractor-trailer they were using on that day did not have a working air conditioning unit. As the temperature rose, the people in the back became desperate, screaming and banging on the walls for help, according to the indictment.

It was the deadliest incident of human smuggling in U.S. history, according to investigators.

Eleven people found inside the tractor were hospitalized but survived, investigators said.

MORE: San Antonio mass death in tractor-trailer highlights dangerous plight of migrants

U.S. Assistant Attorney General Kenneth Polite spoke at length during a news conference about the efforts with Joint Task Force Alpha, whose mission is to investigate human rights violations and push for prosecution. Since June of 2021, they've had 80 convictions.

Chandan Khanna/AFP via Getty Images, FILE
In this June 29, 2022, file photo, people place flowers and candles at a makeshift memorial where a tractor-trailer was discovered with deceased migrants inside, outside San Antonio, Texas.

"Our message is simple," Polite said. "When you put people’s lives at risk, when you ignore the screams of humanity for profit, we will aggressively go after you."

The trial for Zamorano and Martinez is set for Sept. 11. All six charged so far face life in prison if convicted. Attorney information for the suspects wasn't immediately available.