URBANA, Ill. (AP) — One of four Illinois men charged with conspiracy to interfere with commerce by threats and violence has pleaded guilty to the charges.

Ellis Mack of Clarence also pleaded guilty Tuesday to unlawful possession of a machine gun before U.S. Magistrate Judge Eric Long in Urbana.

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Long set the 18-year-old Mack’s sentencing for Jan. 9 before U.S. District Court Judge Sara Darrow.

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As part of his plea agreement, Mack agreed to cooperate with prosecutors in their cases against the other alleged members of the Patriot Freedom Fighters, Michael Hari, Michael McWhorter and Joe Morris. Prosecutors allege the four conspired to rob or attempt to rob Walmart stores, and attempted to extort Canadian National Railway by threatening to damage tracks if the railroad didn’t pay ransom.

The 47-year-old Hari, 29-year-old McWhorter and 23-year-old Morris are charged in Minnesota with the August 2017 bombing of the Dar al Farooq Islamic Center in Bloomington. No one was injured.

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