Terrorism
Prosecutors said Audrey Mondjehi was instrumental to the attack carried out by Islamic State militant Cherif Chekatt.
The alleged culprits behind the deadly shooting in Moscow had ambitions for attacks beyond Russia, according to Western intelligence agencies.
Among those who died in the attack were band superfans, a beauty queen, and two men celebrating their birthdays.
ISIS has claimed responsibility for the attack—which has killed at least 115 people, according to Russian authorities—while Ukraine has denied any involvement in the attack.
U.S. citizens were advised to stay away from all large gatherings in the Russian capital.
Justin Mohn had already been charged with first-degree murder and abuse of a corpse.
The coming year is set to be a trying time for America, at least according to Bruce Hoffman and Jacob Ware, whose new book traces the history of right-wing terrorism in the U.S.