A Lewiston man pleaded guilty in federal court Wednesday to charges of theft from interstate shipments and possession of controlled substances.

Nathan K. Brown, 24, faces up to three years in prison and a $250,000 fine on the theft charge and up to one year and a $1,000 fine on the charge of possession of a controlled substance.

His sentencing is expected after the completion of a pre-sentence investigation report by the U.S. Probation Office, according to a written release by U.S. Attorney Thomas Delahanty II.

Brown worked for the United Parcel Service loading trucks in Auburn. Four times between March 29 and June 19 Brown stole packages that contained prescription pain relief medications, including Percocet and Oxycodone, from trucks he was loading, according to court records.

Those packages had been shipped from a U.S. Department of Veterans Affairs pharmacy to patients in the VA.

On July 2, agents from the VA Office of the Inspector General and the Maine Drug Enforcement Agency, with assistance from UPS workers, caught Brown as he tried to steal a fifth package that contained the prescription medications.

The case was investigated by the VA Officer of the Inspector General, the Maine Drug Enforcement Agency and the U.S. Postal Service Office of the Inspector General.