The U.S. attorney’s office says 28-year-old Stuart Siecke, of Worthing, and 37-year-old Dean Bourn, of Vermillion, obtained the narcotic from co-conspirators in Minneapolis for distribution in South Dakota. Fentanyl is a synthetic opioid drug much more powerful than heroin.

Homeland Security helped in the investigation that led to the two men pleading guilty to drug conspiracy in February. Siecke was recently sentenced to seven years and three months in prison and Bourn to seven years and four months.