Migrants who would soon be abandoned in sweltering and deadly Texas heat were inside a tractor-trailer when it cleared a Border Patrol checkpoint, according to a U.S. official who spoke to The Associated Press.
The official, speaking to the AP on condition of anonymity to discuss an ongoing investigation, said 73 people were inside the truck, including the 53 who died, after the truck was found on the American side of the border Monday.
The truck went through the inland checkpoint 26 miles northeast of the border city of Laredo, Texas, and then proceed to travel more than 100 miles north to San Antonio.
It's unclear whether agents stopped the driver for questioning at the inland checkpoint or if the truck went through unimpeded, bringing into question the effectiveness of border checkpoints.
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One of the suspects charged in connection to the smuggling incident and accused of driving the tractor-trailer from Mexico to San Antonio appeared in court for the first time Thursday.
Homero Zamorano Jr., 45, was arrested Wednesday and charged with one count of smuggling resulting in death in connection to the suspected migrant smuggling operation, according to the U.S. Attorney’s Office in the Western District of Texas.
During Thursday's hearing which lasted about five minutes, Zamorano said very little. U.S. Magistrate Judge Elizabeth Chestney appointed him a federal public defender, as well as a second attorney because the smuggling charge he faces carries a possible death sentence.
Laredo Sector Border Patrol agents provided Homeland Security Investigations with surveillance footage of the tractor-trailer crossing through an immigration checkpoint, the office said. The footage led San Antonio Police Department officers to where Zamorano was found hiding in the brush after trying to run away, according to the office.
Zamorano is originally from the south Texas city of Brownsville, near the state's border with Mexico, but he resides in Pasadena, Texas, prosecutors said. If convicted, he faces up to life in prison or the death penalty.
Three others were also arrested and are in federal custody.
Christian Martinez, 28, was arrested Tuesday in Palestine, Texas, and faces a charge of conspiracy to smuggle resulting in death, according to prosecutors. Investigators found evidence on Zamorano's phone that he had communicated with Martinez about the suspected smuggling conspiracy beforehand, prosecutors said.
Martinez had his first court appearance Wednesday. If convicted, he could also face up to life in prison or the death penalty.
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Juan Claudio D'Luna-Mendez, 23, and Juan Francisco D'Luna-Bilbao, 48, who are Mexican citizens, both face a charge of possessing a weapon while in the U.S. illegally, federal charging documents filed in the Western District of Texas show.
Court records show the two men have not been charged in the suspected smuggling plot. Prosecutors say investigators located D'Luna-Mendez and D'Luna-Bilbao by tracing the addresses on the vehicle's registration.
Authorities found a handgun in the truck D'Luna-Bilbao was driving and additional firearms in the residence. Both men admitted to possessing illegal firearms and to overstaying their visas, according to the complaints.
Both men are scheduled to appear in court Friday.
Contributing: Jeanine Santucci, USA TODAY; The Associated Press
This article originally appeared on USA TODAY: San Antonio suspected migrant smuggling plot: Suspect to be in court