A 20-year-old Glendale man has been arrested and charged with possessing with intent to distribute fentanyl, authorities said.

David Quintero-Mascareno, 20, was arrested July 1 after a Customs and Border Protection canine trained to detect narcotics alerted officers stationed a the Lukeville Port of Entry, according to a release from the Arizona district of the U.S. Attorney’s Office.

A complaint alleges that Quintero-Mascareno drove to the entry point in a gray Dodge Ram towing a trailer loaded with a utility terrain vehicle.

Quintero-Mascareno said he was returning to the United States from Puerto Penasco, Sonora, Mexico, and “gave a negative customs declaration for contraband,” the release stated.

After being alerted by the canine, CBP officers found approximately 234 packages, containing blue pills imprinted with “M30,” concealed in the trailer’s floorboards and rails, officials said.  A field test of a representative sample of the pills tested positive for the properties of fentanyl. The packages weighed a total of nearly 460 kilograms.

A conviction for possession with intent to distribute 400 grams or more of fentanyl carries a maximum penalty of life in prison, a fine of $10 million, or both, and a maximum term of five years supervised release, according to the U.S. Attorney’s Office.

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