The Justice Department on Tuesday announced new charges against four Americans in Florida and three Russians for allegedly working on behalf of the Russian government "to conduct a multi-year foreign malign influence campaign in the United States."

The superseding indictment from a federal grand jury in Tampa adds charges to Moscow resident Aleksandr Viktorovich Ionov and Russian Federal Security Service (FSB) officers Aleksey Borisovich Sukhodolov and Yegor Sergeyevich Popov, the department said.

Additionally, a separate unsealed case in Washington charges Russian national Natalia Burlinova "with conspiring with an FSB officer to act as an illegal agent of Russia in the United States."