SAN ANTONIO — Dozens of migrants were found dead in an abandoned big rig in San Antonio on Monday in what appears to be the deadliest human smuggling case in modern U.S. history.
The tragedy's death toll rose to 51 on Tuesday afternoon, Bexar County officials said at a news conference, and some of the deceased could be teenagers who never reached adulthood.
Most of the victims were found dead in the tractor-trailer in the sweltering Texas heat, officials said.
Contributing to the number of deceased Tuesday was the demise of three patients being treated at Baptist Medical Center, where two survivors remained in critical condition, hospital spokesperson Patti Tanner said.
Sixteen people, including four children, were initially hospitalized, San Antonio Fire Chief Charles Hood said. None of those children have died.
The dead include 39 males and 12 females, Bexar County officials said at an afternoon news conference. Tom Peine, the assistant public information officer for the county manager's office, said it was possible some had not reached adulthood.
"Potentially some of them are under the age of 18," he said. "These are potentially people under 18 — I would say in the teenage age range, not younger."
The regional medical examiner would likely be able to identify 34 of the deceased at this point in the investigation, officials said.
On Tuesday morning, Mexican President Andrés Manuel López Obrador said 22 of the dead were Mexican nationals, while seven were from Guatemala and two from Honduras. The nationalities of the remaining 20 people had yet to be confirmed.
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López Obrador said the Mexican government would be providing assistance to the family members of the dead.
Three people were taken into custody following the discovery, San Antonio Police Chief William P. McManus said, though he added authorities did not know if they were definitely connected to the incident. He did not expand on their identities.
The grim find was made early Monday evening in an undeveloped area of southwest San Antonio near railroad tracks. A person who works in the area reported hearing a cry for help and spotted at least one body, officials said.
Homeland Security Investigations responded to the incident on Quintana Road near Cassin Road following a call from the San Antonio Police Department and found more than 40 deceased individuals at the scene, U.S. Immigration and Customs Enforcement said Tuesday in a statement.
"We're not supposed to open up a truck and see stacks of bodies in there," Hood said.
McManus said the survivors lacked water and air conditioning. "The patients that we saw were hot to the touch," he said. "They were suffering from heat stroke, heat exhaustion."
McManus said Homeland Security Investigations had taken over the investigation into the deadly incident. The heat is likely to be a focus, with temperatures climbing to 101 Monday, according to the National Weather Service.
The heat inside the trailer packed with people was likely to have been significantly higher than the outside temperature.
A committee of the National Association of Medical Examiners has recommended that bodies with temperatures of 105 or greater at the time of collapse be certified as heat-related deaths.
Methodist Hospital Metropolitan in downtown San Antonio is treating three patients, described by officials as two males and one female who are listed in critical but stable condition. The hospital has been unable to verify their ages.
Meanwhile, University Hospital in San Antonio is treating two patients: a 23-year-old woman in serious condition and an adolescent male in critical condition, hospital spokesperson Andra Wazir said.
County Commissioner Rebeca Clay-Flores said the woman, from Guatemala, was improving and was able to speak, but that the condition of one teenage survivor at University Hospital was dire.
"We are asking for prayers for him," she said at the news conference.
Two Mexican nationals at Texas Vista Medical Center are "dehydrated, receiving medical care now," Mexican Foreign Minister Marcelo Ebrard said on Twitter.
J. Antonio Fernandez, CEO of Catholic Charities in San Antonio, and Archbishop Gustavo García-Siller, who leads the archdiocese of San Antonio, visited the University Hospital patients.
Fernandez could not confirm the patients' names or ages.
They were intubated and had many other tubes connected to them. The male patient could not speak but he was wearing a scapular, a Catholic religious accessory that goes around the neck, he said.
There was security posted for the female patient but not for the male patient, Fernandez noted.
He and García-Siller asked her if they could pray for her and she nodded her head, Fernandez said.
They asked if she was from Guatemala and she nodded again, he said.
"It was a nice experience to end the day that way," Fernandez said.
Dennis Romero reported from Los Angeles, Suzanne Gamboa from San Antonio, Chantal Da Silva from London and Rhoda Kwan from Taipei.