One of three men newly charged with distributing heroin on a northern Minnesota Indian reservation is also accused of fatally shooting two armed robbers when they tried to steal the trafficking operation's drugs, authorities said Thursday.

Indictments were unsealed in federal court against Franklin Jackson, 23, Kristopher Sullivan and Bryan Boardman, both 24. All three are in federal custody.

The indictments offer scant details about the allegations but zero in on the first three weeks of October, when the defendants allegedly conspired to distribute "a mixture of substance containing a detectable amount of heroin," the indictment read.

Some specifics about the killings, however, were spelled out during a detention hearing for Boardman this week.

Boardman and Sullivan brought a trailer holding heroin from the Twin Cities to the reservation and were confronted on Oct. 21 by two adults with long guns, an FBI agent testified.

In response, Boardman shot the two, identified by law enforcement as James Rojas III, 32, and Dustin R. Barrett, 26. A third person with Rojas and Barrett survived being shot. That person has not been identified.

Jackson, Sullivan and Boardman were charged with conspiracy to distribute heroin. Boardman and Sullivan also were charged with use of a firearm during a drug-trafficking crime for their alleged roles in the killings. Authorities would not say whether charges would be filed in connection with the deaths.

Attorneys for the defendants either declined to comment or did not respond to requests for a response to the allegations.