Two Duluth men were charged with a 15-count indictment in connection to drug distribution on Friday.

Eric A. Black, 36, and Otis J. Weaver, 39, were charged in U.S. District Court with heroin distribution conspiracy, according to a news release from the U.S. Attorney’s Office in the District of Minnesota.

During a period in March, Black and Weaver worked with others to plan the distribution of over 1 kilogram of heroin, the release reads. They then allegedly distributed heroin between March 10-20.

Black has felony convictions in Cook County, Illinois and LaPorte County, Indiana. He was charged with one count of conspiracy to distribute heroin, nine counts of distribution of heroin, one count of possession with intent to distribute heroin, one count of possession with intent to distribute cocaine, one count of felon in possession of a firearm, and one count of possession of a firearm in furtherance of a drug trafficking crime.

Weaver was charged with one count of conspiracy to distribute heroin, nine counts of distribution of heroin and one count of possession with intent to distribute heroin.

The charges resulted from an investigation by the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives, U.S. Drug Enforcement Administration, Minnesota Bureau of Criminal Apprehension and Duluth Police Department. The Project Safe Neighborhoods — an initiative to combat violent crime — connected the numerous departments together to work on the case, the press release reads.

The Duluth men will be arraigned on the charges at a later date.