SAN ANTONIO (AP) - Authorities say the driver of a semitrailer found outside a San Antonio Walmart in July packed with immigrants, including 10 who died, faces additional charges in the smuggling case and another defendant has now been charged.

The U.S. attorney's office in San Antonio says a grand jury returned the superseding indictment Wednesday. U.S. Attorney Richard Durbin Jr. says he won't seek the death penalty against the driver, James Bradley Jr. Bradley faces up to life in prison.

Prosecutors say the indictment also alleges 47-year-old Pedro Silva Segura of Laredo, who is in the U.S. illegally, transported immigrants and tried to shield them from detection. He could face up to life in prison or death penalty.

It was unclear if Silva had an attorney. An attorney for Bradley had no comment.

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