SAN ANTONIO — The alleged driver of the tractor-trailer involved in the deadliest human smuggling incident in U.S. history made his first court appearance in federal court in San Antonio.
He and another U.S. citizen could face the death penalty for their role in the deaths of 53 people.
Court documents reviewed by KHOU 11 News provide a better picture of the moments leading up to that gruesome discovery in San Antonio.
Text messages sent by the alleged driver, Homero Zamorano, helped federal investigators track down those responsible.
According to the criminal complaint, Zamorano was caught on CBP cameras driving the 18-wheeler through a checkpoint near Encinal, TX. Hours after that photo was taken, law enforcement discovered 48 dead in the semi-truck. Five would later die at local hospitals including several children.
Zamorano was spotted by police in a nearby field pretending to be one of the survivors. He's now charged with smuggling leading to the deaths of 53 people.
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Christian Martinez is also in federal custody. He's the man who investigators say repeatedly texted Zamorano that day.
At 12:17 p.m. Martinez sends Zamorano a photo of a truck manifest.
Two minutes later at 12:19 p.m., Zamorano responds, "I go to same spot".
Martinez then sends him GPS coordinates of a location near Laredo, TX.
By 1:40 p.m. Martinez texts Zamorano, "Way bro", believed to be a typo for "where you at."
Martinez never hears back from Zamorano, repeatedly following up with "call me bro" and "wya" around 6:17 p.m.
By that time first responders had descended on the scene and Zamorano was under arrest.
RELATED: Authorities: Big rig driver in deadly human smuggling case pretended to be among the injured
Court docs reveal Martinez admitted to his role in the smuggling event. He told a confidential informant the driver did not know the A/C unit was not working on the truck.
The medical examiner's office in Bexar County is still working to ID victims but some families have already been notified in their home countries, including seven Guatemalans.
Manuel Tulul lost his 13-year-old son Wilmer in the trailer. He says they were charged $6,000 by smugglers to get his son to the U.S. He begged his son not to go.
"I told him, you stay here, I work and feed you, but he told me he needed to go struggle. He wanted his house, he wanted something," Manuel said.
Martinez and two other Mexicans charged in the smuggling cases are expected in court by the end of the week.