A Minneapolis drug dealer has been sentenced to a lengthy prison term for selling heroin that killed a 19-year-old woman in Little Falls, Minn.

Keon “Bird” Mangun, 30, was sentenced Monday in Morrison County District Court to a term of 11 years and two months, with at least two-thirds of the time to be served in prison. Jurors two months ago found Mangun guilty of third-degree murder in the Feb. 28, 2012, death of Miranda Gosiak of rural Little Falls.

Assistant County Attorney Todd Kosovich, who prosecuted Mangun, called the verdict “a major victory in the war on heroin. In this case, we went after the heroin dealer himself.”

He said it was his office’s first murder conviction of a defendant who sold an illicit drug to a buyer who then provided it to the victim. He said he’s aware of a couple of other recent cases in the state, but those convictions came by plea bargains.

Two other people have been convicted of felonies in Gosiak’s death.

Prosecutors say that Mangun sold heroin to Brandon Bedford in north Minneapolis the day before Gosiak died. Bedford provided the heroin to Gosiak, who overdosed at the home of Tanya Ashby, 39, and her boyfriend, Christian Dahn, 31.

Bedford, 26, who lived upstairs in the home where Gosiak died, remains jailed in lieu of $1 million bail on a charge of aiding and abetting third-degree murder.

Dahn pleaded guilty to felony drug possession and testified against Mangun in return for a one-year jail sentence and 20 years of probation, rather than four years in prison.