A group of people were found in a trailer and taken to a hospital. There were 16 people, including four children, according to France 24. Some of the people in the trailer are from Mexico. According to The New York Times, the nationalities of some of the deceased have not been confirmed.

The people in the trailer seemed to be suffering from heat stroke, heat exhaustion and dehydration. San Antonio Fire Chief Charles Hood said at the press conference that there was no water or air conditioning in the truck.

It was a hot day in San Antonio, with the temperature reaching the high 90s to low 100s. San Antonio Police Chief William McManus told The Texas Tribune that this was the worst human smuggler incident he had ever seen in the city. In July of last year, 10 people died inside of a tractor-trailer outside of a Walmart.

As the American Southwest sees record breaking daytime and nighttime temperatures, it could become more common for migrants to die trying to get into the country. Dehydration is the main cause of death for migrants crossing the U.S. Mexico border. Many of the people that make the dangerous trek north carry water and food with them, but they often don't have enough to survive the harsh conditions that they have to endure. Climate change is expected to cause more deaths in the area as it gets hotter.

The risk to survivors of the incident will be decided by how long they were stuck in the hot trailer. She said that if the migrants were conscious, they would be stable quickly in the hospital.

She said that a large majority of people have a full recovery from heat exhaustion. It may take longer for you to recover from illness.