PROVIDENCE, R.I. (AP) — A man who admitted to having more than 665,000 counterfeit Adderall pills containing methamphetamine has been sentenced to 10 years in federal prison.

Dylan Rodas, 27, of Cumberland, Rhode Island, pleaded guilty in September to possession with intent to distribute 500 grams or more of methamphetamine. He was sentenced on Thursday.

It is believed to be the largest seizure of methamphetamine-laced fake Adderall pills in the U.S., as well as among the largest seizures of methamphetamine in DEA New England Field Division history, said Zachary Cunha, U.S. attorney for Rhode Island.

Adderall is a prescription medication used primarily to treat attention deficit hyperactivity disorder.

The drugs, with a street value of about $4.6 million, were seized during two court-authorized searches in Cumberland last March.

Authorities also found a bucket containing 40 pounds (18 kilograms) of meth mixture prepped and ready to be pressed into pill form, two pill presses that can manufacture about 5,000 pills per hour each, $15,000 cash and multiple handguns, including two ghost guns and two that had the serial numbers obliterated, Cunha said.