Four survivors of the deadly smuggling attempt that killed 53 migrants in San Antonio remain hospitalized, with two of them in critical condition.

A former Homeland Security investigator said the survivors will need to recover to help with the investigation. 

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When deaths are involved in human smuggling investigations, surviving migrants become key witnesses to find those responsible, Harry Jimenez said.

“As material witnesses… they will stay in the United States,” Jimenez said. “They will be provided with some type of relief."

Jimenez said survivors are granted a special visa to live and work in the U.S. while the case moves along.

It’s likely the accused driver in the San Antonio tragedy - Homero Zamorano - will be locked-up for the rest of his life or face the death penalty.

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