PORTLAND -- A citizen’s complaint has led a pot-dealing postman from package delivery to prison time.

Ronald Berkan, a 48-year-old postman in Veronia, Ore., was sentenced Tuesday to 18 months in prison, following his guilty plea last April on one charge of marijuana distribution to a person under 21 years old.

The delivery occurred on his mail route in the Cedar Mill area of Washington County.

As part of the sentence, almost $3,000 of drug proceeds Berkan had collected was also forfeited.

The legal investigation began in 2006 when federal authorities received a citizen’s complaint that a uniformed postal carrier was offering marijuana for sale on his route.

Berkan was identified by the U.S. Postal Service Office of the Inspector General. Drug Enforcement Administration officials subsequently joined in an investigation that lasted 11 months, according to the U.S. Attorney for the District of Oregon.

Federal authorities executed a warrant at Berkan’s residence earlier this year, where they also found 47 marijuana plants and almost nine pounds of cultivated pot.

“A significant break in the investigation occurred when Lake Oswego Police Department arrested a 19-year-old who had been buying marijuana from Berkan since the buyer was in high school,” said a press release from U.S. Attorney Karin Immergut.

Berkan resigned from the postal service, where he’d been employed 15 years, as part of his sentencing deal.

“Postal carriers are trusted by the public to be honest and upstanding in carrying out their duties,” Immergut said. “In this case, not only did the defendant violate that public trust by dealing drugs on his mail route, but he also sold drugs to a person under 21 years of age.”

A special agent with the postal service commented on the Berkan sentencing Monday, saying the government considers drug use, possession or distribution by postal employees “a serious crime.”

KGW Reporter Kyle Iboshi contributed to this report.