25-year-old Miguel Romero Reyes is from Sinaloa, Mexico.
Reyes faces federal charges of possessing more than 400 grams of fentanyl with intent to distribute.
Fresno County Sheriff's deputies stopped him as he was driving north on Interstate 5.
They seized a large duffel bag containing 48 pounds of blue counterfeit M30 pills in more than a dozen 1-gallon Ziploc bags.
According to court documents, Reyes conspired with another person to distribute the drugs.
If convicted, he faces a minimum of 10 years in prison.
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