The man suspected to have been driving the truck in which dozens of migrants died during a people smuggling attempt in Texas pretended to be a survivor to try to avoid arrest.
Homero Zamorano Jr, 45, was arrested near the scene after he was found hiding in a bush, according to federal prosecutors.
The head of Mexico’s National Migration Institute Francisco Garduno said on Wednesday that he “tried to pass himself off as one of the survivors” when he was detained in San Antonio.
Zamorano and a second suspect, Christian Martinez, 28, have both been charged for their alleged involvement in the deaths of 53 migrants.
Martinez was charged with a single count of conspiracy to transport illegal aliens, while Zamorano has been charged with one count of alien smuggling resulting in death.
If guilty, both face life sentences in prison, or the death penalty, the US Justice Department said.
The truck was carrying migrants from Mexico, Guatemala, Honduras and El Salvador.
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It was found abandoned on Monday on the outskirts of San Antonio, with officials finding the back door of the truck ajar with “stacks of bodies” inside, many of them hot to the touch.
As well as 53 deaths, a further 11 people, including children, remain in hospital.
Temperatures in the area that day were recorded at 103F (39.4C) and authorities said they found no water supplies or signs of working air conditioning inside the cargo trailer.
While Zamorano was arrested at the scene, Martinez was detained after investigators linked him to the truck driver through Zamorano’s mobile phone.
Migrants boarded on US soil
Mexican nationals Juan Francisco D’Luna-Bilboa and Juan Claudio D’Luna-Mendez have also been charged as suspects.
A preliminary hearing is expected to take place on Friday.
Of those who died, 27 were from Mexico, 14 from Honduras, seven from Guatemala and two from El Salvador, according to Mexico’s government.
The majority of the dead were male, but 13 were women, Bexar County medical examiner’s office said.
Surveillance footage shows the moment the lorry passed through a border checkpoint in Laredo, Texas on Monday before the migrants are believed to have boarded.
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“The migrants were already on US soil,” before entering the truck, Mr Garduno said.
The lorry reportedly passed two further border cameras in Texas as it moved deeper into US territory.
The migrants are likely to have crossed the border in smaller groups before being held in a safe house in Texas and then placed in the lorry to be moved further into the US, according to a source at Mexico’s migration institute.