The Brownsville native accused of being involved in the nation's deadliest human smuggling attempt is being held without bond.

A federal judge in San Antonio ordered Homero Zamorano to be held without bond pending trial.

Zamorano is accused of driving the big rig where 53 migrants died last week.

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Authorities say the migrants were left in the back of an 18-wheeler in the heat without water or A/C.