San Antonio Mayor Hopes for Justice Following 'Horrific Human Tragedy' of Tractor-Trailer Deaths

Mandatory Credit: Photo by Eric Gay/AP/Shutterstock (13008136h) San Antonio Mayor Ron Nirenberg, center, with San Antonio Police Chief William McManus, left, brief media and others at the scene where they said dozens of people have been found dead and multiple others were taken to hospitals with heat-related illnesses after a semitrailer containing suspected migrants was found, in San Antonio Migrant Deaths, San Antonio, United States - 27 Jun 2022

Eric Gay/AP/Shutterstock

San Antonio Mayor Ron Nirenberg has spoken out on the horrific discovery inside of an 18-wheeler in the southwest part of the city. As of Tuesday, the death toll is now 50.

"This is nothing short of a horrific human tragedy," Nirenberg said during a press conference Monday. "I would urge you all to think compassionately and pray for the deceased, the ailing, the families."

"Our job is not to ask why. Our job is to ask how we can help," he continued. "That's why you're seeing medical assistance. As far as the federal investigation goes, that's in the hands of the feds. I'm sure there will be more questions and hopefully some answers as we move forward."

The mayor wrapped his remarks by sharing his hopes for the findings of the investigation.

"We hope that those responsible for putting these people in such inhumane conditions are prosecuted to the fullest extent of the law," Nirenberg said.

RELATED: 46 People Dead, 16 Hospitalized After Being Found Inside 18-Wheeler in San Antonio

The floor was then passed to San Antonio Fire Chief Charles Hood, who echoed similar sentiments about the harrowing situation.

"We're not supposed to open up a truck and see stacks of bodies in there," Hood said. "None of us come to work imagining that."

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As of 6 a.m. Tuesday, the total number of deceased is 50, and Homeland Security Investigations has detained three individuals believed to be part of the alleged smuggling conspiracy, a U.S. Immigration and Customs Enforcement spokesperson tells PEOPLE.

Marcelo Ebrard, Mexico's secretary of foreign affairs, also tweeted that the death toll had risen to 50 people.

"50 deceased. 22 Mexicans. 7 Guatemalans. 2 Hondurans. The others are yet to be identified," he wrote. "We are in mourning [sic]. Huge tragedy. Mexico joins investigations in the US, coordinated with DHS."

An additional 16 people (12 adults and four children) were rushed to nearby hospitals in varying conditions Monday after multiple police, fire trucks and ambulances responded to the scene at the 9600 block of Quintana Road, authorities confirmed during Monday's press conference.

Two were admitted to University Hospital and at least five were brought to Baptist Medical Center in unknown conditions, PEOPLE confirmed.

Mandatory Credit: Photo by Eric Gay/AP/Shutterstock (13008136a) Body bags lie at the scene where a tractor trailer with multiple dead bodies was discovered, in San Antonio Migrant Deaths, San Antonio, United States - 27 Jun 2022
Mandatory Credit: Photo by Eric Gay/AP/Shutterstock (13008136a) Body bags lie at the scene where a tractor trailer with multiple dead bodies was discovered, in San Antonio Migrant Deaths, San Antonio, United States - 27 Jun 2022

Eric Gay/AP/Shutterstock

Chief Hood said that the victims, who are believed to be undocumented migrants, "were hot to the touch." He added, "They were suffering from heat stroke, heat exhaustion. No signs of water in the vehicle. It was a refrigerated tractor-trailer but there was no visible working AC unit on that rig."

Temperatures in San Antonio reached a high of 103 degrees on Monday.

The 16 taken to the hospital are expected to survive, Hood said, also noting that no children are among the deceased.

It is not clear how many people were in the tractor-trailer when it was abandoned near train tracks and an auto salvage yard. Not everyone has been accounted for.

Hood added that number of individuals "got out."

Three people are in custody, but it's not clear if they're connected to the incident, Chief William P. McManus said during the press conference.

Mandatory Credit: Photo by Eric Gay/AP/Shutterstock (13008136a) Body bags lie at the scene where a tractor trailer with multiple dead bodies was discovered, in San Antonio Migrant Deaths, San Antonio, United States - 27 Jun 2022
Mandatory Credit: Photo by Eric Gay/AP/Shutterstock (13008136a) Body bags lie at the scene where a tractor trailer with multiple dead bodies was discovered, in San Antonio Migrant Deaths, San Antonio, United States - 27 Jun 2022

Eric Gay/AP/Shutterstock

On Monday, a U.S. Immigration and Customs Enforcement (ICE) spokesperson told PEOPLE, "On June 27, Homeland Security Investigations (HSI) responded to a call from San Antonio Police Department (SAPD) in reference to an alleged human smuggling event involving a tractor trailer on Quintana Road near Cassin Road. Upon arrival in the scene, HSI confirmed more than 40 deceased individuals."

They added, "HSI continues its enforcement efforts to ensure the safety and well-being of our communities. We will continue to address the serious public safety threat posed by human smuggling organizations and their reckless disregard for the health and safety of those smuggled. To report suspicious activity, we encourage people to call the HSI Tip Line at 1-866-DHS-2ICE. All calls are kept confidential."

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The San Antonio Fire Department confirmed to PEOPLE that this is "an active and ongoing incident" with the investigation being led by Homeland Security Investigations (HSI).

Homeland Security Investigations San Antonio confirmed to PEOPLE the agency is on scene and will lead a federal investigation.

HSI San Antonio has initiated the investigation with support of SAPD. Details will be released as they are available, and the criminal investigation remains ongoing.