Russia claims that the 12 are members of a neo-Nazi cell. Two of them allegedly planned to assassinate Margarita Simonyan, editor-in-chief of the state-controlled Russian channel RT.
Simonyan is a staunch supporter of President Vladimir Putin. She is considered one of the country's most powerful media executives and has shown strong support for the war in Ukraine.
The group's 21-year-old leader has been sentenced to 20 years in prison, while the other 11 convicted will receive prison terms of between 6 and 18 years, according to Russia's State Investigative Committee.
The trial was held behind closed doors and no details about the suspected murder plans have been made public.
The 12 were also accused of attacks against migrants and LGBTQ people, as well as robbery and incitement against an ethnic group.
