FILE PHOTO - Then FBI Director Robert Mueller testifies at a Senate Intelligence Committee hearing on Capitol Hill in Washington, DC, U.S. on February 16, 2011. REUTERS/Jason Reed/File Photo

WASHINGTON (Reuters) - A federal grand jury in Washington on Friday approved the first charges in the investigation led by special counsel Robert Mueller into alleged Russian meddling in the 2016 U.S. presidential election, a source briefed on the matter told Reuters.

The filing of the sealed charges was first reported by CNN.