Early Sunday morning, eight people were found dead inside an 18-wheeler trailer that was parked at a Walmart in San Antonio, Texas.
The San Antonio police department and fire department are working a scene in the Walmart parking lot located on Interstate 35 and Poteet Jourdanton Highway. The Department of Homeland Security has also joined the investigation.
While investigators did not know where the truck had driven from, the police chief said such operations were routine in the area - often going undiscovered in the darkness.
The employee gave the person the water and then called police. The survivors, McManus said, will be investigated by Immigration and Customs Enforcement.
There were 38 people - including two 15-year-olds - trapped in the refrigeration truck-turned-coffin, which lacked air conditioning amid a day of 100-degree temperatures Saturday.
As it was, Hood said, 30 were hospitalized - 17 in critical condition. He later added that emergency workers used triage techniques to help people in what he called a "mass-casualty" event.
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Bicking said he favored a policy in which there would be less officer discretion for when the cameras should be turned on and off. The two officers' body cams were not switched on and footage from the police auto failed to capture the incident .
McManus said officers arrested the truck driver, who was not immediately identified but would likely face state and federal charges.
Hood said EMS transported patients ranging in age from young children to adults in their 30s to seven different area hospitals, sending a large number downtown. 30 people were also discovered in the truck.
"Our paramedics and firefighters found that each one of them had heart rates over about 130 beats per minutes", he said.
San Antonio is a few hours' drive from the border with Mexico's Nuevo Leon state, and illegal immigration into the U.S. is a daily occurrence. It's believed that they were illegal immigrants and the victims of human trafficking.
McManus urged anyone who encounters potential instances of human trafficking, or individuals who appear to be fleeing such conditions to call 911. McManus stressed that it was not an isolated incident. "Fortunately we came across this one; fortunately there are people who survived".
"We are very fortunate that there weren't 38 people who were locked inside of this vehicle dead", he says.