A federal grand jury has indicted two Twin Cities men in connection with an alleged yearlong conspiracy to distribute the deadly synthetic opioid fentanyl, a case that included the seizure of more than $14,000 and multiple firearms, according to charges unsealed this week.

Matthew James Dolimpio and Dwayne Lamonte Greer, Sr., will be arraigned in federal court in St. Paul on Friday on charges outlined in a seven-count indictment.

Messages were left seeking comment from attorneys for both men.

Dolimpio, 36, of St. Louis Park, and Greer, 45, of Minneapolis, are accused of a carrying out the distribution scheme in 2016. Greer also is charged with carrying a handgun "during and in relation to a drug trafficking crime." The grand jury returned its indictment last month, and a federal judge made the case public on Wednesday.

Black market fentanyl, an extremely powerful opioid, is typically found mixed into heroin.

Investigators also seized $14,812.35 from the two last year. During the Nov. 3, 2016, search, authorities seized three firearms and ammunition.