A Boise woman who helped a gang member broker the sale of two sawed-off shotguns to a federal informant at a city park for $600 in May pleaded guilty to a federal gun charge Wednesday.

Christina Shantell Massie, 35, faces up to 10 years in prison and three years of probation when she's sentenced Feb. 25 at by U.S. District Judge Lynn Winmill in Boise for possessing an unregistered firearm.

Co-defendant Joshua Michael Trent, 31, pleaded guilty last month to possessing an unregistered firearm and is to be sentenced Feb. 5.

Massie and Trent are among 21 people charged in a federal investigation into the Aryan Knights, a gang said to be responsible for the distribution of methamphetamine in Idaho.

Massie also has a previous felony conviction for possession of a controlled substance with the intent to deliver, according to U.S. Department of Justice reports.

According to the U.S. Attorney's Office, 13 of the 21 people indicted face drug charges, including four counts of conspiracy to distribute methamphetamine, 15 counts of distributing methamphetamine, and four counts of possessing methamphetamine with the intent to distribute. Eight were indicted on firearm charges, including six counts of unlawfully possessing firearms, two counts of possessing sawed-off shotguns, and one count of transferring a sawed-off shotgun. Two were indicted on both drug and firearms charges, including two counts of distributing methamphetamine and two counts of unlawfully possessing firearms.

Those charged include Andrew Gallegos, 23, Jose Silva, 30, Shannon L. Stewart, 41, and Michael P. Duschka, 36, all of Boise. Thirteen were indicted on September 12, including Dallas Tyler Thompson, 31, Cameron James Ball, 25, Joshua Michael Nall, 31, Nicholas Andrew Steele, 26, Lisa Rochel Samayoa, 45, Jesse Ray Delgado, 47, Stephanie Ann Robinson, 29, and Dennis Lynn James, 45, all of Boise; Christopher John Solders, 26, and Darin Scott Melton, 44, both of Twin Falls, Idaho; Nina Ann Lucas, 32, of Pocatello, Idaho; and Mexican nationals Rigoberto Bastrana Carrasco, 36, of Ogden, Utah, and Omar Riveroll-Hernandez, 32, of Long Beach, Calif.

At least four people charged in connection with the case have entered guilty pleas.