Eight people have been found dead in a tractor-trailer outside a Walmart in San Antonio, Texas, in what police are calling a horrific human trafficking case. Some 30 other people were found in the truck, which didn't have a working air conditioning system, and they were taken to hospitals, reports CNN. Seventeen of them are in critical condition, while 13 are in serious condition. Authorities said the driver had been held, but they didn't release the driver's identity. A person from the truck approached a Walmart employee in a parking lot and asked for water late Saturday or early Sunday, San Antonio police said. The employee gave the person the water and then called police, reports the AP, and when officers arrived they found the eight people dead in the back of the trailer, police Chief William McManus said.
Investigators checked store surveillance video, which showed vehicles had arrived and picked up other people from the tractor-trailer, police said. "We're looking at a human trafficking crime this evening," McManus said. He called the case "a horrific tragedy." The US Department of Homeland Security was involved in the investigation into what happened, he said. (Read more human trafficking stories.)