Christian Martinez, 28, was arrested Tuesday on a trafficking charge involving death that could lead to life in prison or the death penalty after the migrants reportedly battled grueling temperatures of up to 150 degrees inside the truck. Martinez’s string of messages with the alleged driver of the semi, 45-year-old Homero Zamorano Jr., was detailed in a criminal complaint obtained by The Daily Beast on Friday. The complaint says the first text came at 12:17 p.m. on Monday, when Martinez texted his alleged accomplice a photo of the pickup truck’s “manifesto.” Zamorano reportedly replied two minutes later: “I’m going to the same spot.” San Antonio police found the semi truck abandoned next to railroad tracks in a rural area outside of San Antonio.

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After 30 minutes, the complaint says, Martinez responded by texting Zamorano: 3108 Chacon Street in Laredo, Texas—an industrial area just three miles from the Mexican border. But there would be no additional responses from Zamorano. This caused Martinez to become seemingly frantic, pestering his partner with a volley of unanswered texts. The complaint says he texted a short version of “where are you bro?” at 1:40 p.m Martinez allegedly texted three more times at 3:18 p.m. He sent: “Call me bro,” “Yeah,” “Call me bro.” Feds say Martinez sent a final message at 6:17 p.m., again sending the initials: “Wya?” As Martinez texted, authorities say Zamorano drove the big rig through the Laredo checkpoint — where it was captured on security cameras — and headed toward the rural, southwest edge of San Antonio. It appears the 73 migrants boarded the truck in or near Laredo on Monday and had their phones confiscated, some family members told The Associated Press. Homero Zamorano, 45, was caught on security cameras driving through a Laredo-area checkpoint.

National Institute of Immigration

Authorities say Zamorano, for unknown reasons, abandoned the truck next to railroad tracks in San Antonio around 6 p.m. Monday. People nearby heard the survivors’ screams and called 911. When San Antonio police responded, they made a gruesome discovery: piles of corpses, warm to the touch, spread out in the back of the truck and spilled onto the road and into the surrounding brush. “I’ve got too many bodies here,” one responding officer said over the radio, the San Antonio Express-News reported. The complaint said Zamorano, who was found in nearby brush, attempted to impersonate the victim. However, first responders didn’t buy it and took him into custody while transporting the truck’s survivors to local hospitals. Zamorano faces the same charge and possible sentence as Martinez for his role in what is being described as the deadliest smuggling incident in US history. Facebook accounts for Zamorano and Martinez list the pair as friends. Martinez’s profile says he worked at Walmart, while Zamorano’s page lists him as single and from Brownsville, Texas—another city on the US-Mexico border. Also arrested in connection with the tragedy were Mexican nationals Francisco D’Luna-Bilbao and Juan Claudio D’Luna-Mendez, after authorities found them at an address linked to the big rig. They were arrested on charges of possessing weapons while residing illegally in the US — a charge punishable by a maximum of 10 years in prison. Martinez, who appears to live in a modest weatherboard home in Palestine, Texas, was already being investigated by Homeland Security, the criminal complaint said. After the truck was discovered Monday, authorities say Martinez admitted to a confidential informant before his arrest that he was involved and that he didn’t know the truck’s AC was out. He also said Zamorano – whom he called “Homer” – tried to elude authorities. In terms of casualties, 27 Mexicans, 14 Hondurans, seven Guatemalans and two Salvadorans have been confirmed dead, according to Francisco Garduño, head of the Mexican government’s National Migration Institute. Families from Mexico and Central America have since taken to social media to remember their loved ones, while authorities in the US have yet to release any identities. The deaths, followed by a car crash that killed four migrants days later in Texas, have reignited a tense debate in the US over immigration at the country’s southern border. Texas Gov. Greg Abbott, a Republican candidate for re-election, was quick to blame President Joe Biden for Monday’s tragedy. “These deaths are for Biden,” Abbott tweeted Monday night. “It is a result of his deadly open border policies. They show the deadly consequences of his refusal to enforce the law.” Elsewhere in Texas, meanwhile, immigration groups pointed the finger the other way, citing strict immigration laws as the reason immigrants seeking a better life in America must put their lives first — and often , their savings- in the hands of smugglers. “We are horrified and dismayed by the horrific and tragic loss of life last night in our community here in San Antonio,” said RAICES San Antonio, a refugee and immigrant center. “At least 50 lives have been lost because of an immigration system that dehumanizes and criminalizes those seeking asylum within our borders.”