Transcript for Investigators: Russian trolls set up fake groups to organize real activists

Now to new developments in the Russia investigation. This morning we're learning Russian interference went beyond the election and included an effort to stir up racial tension here in the U.S. Our chief investigative correspondent Brian Ross is here with more on all that. Good morning, Brian. Reporter: Good morning, robin. If you thought the Russians had stopped their active measures against the U.S., they haven't and they've not only been duping them to stoke racial tensions. ??? Black matters U.S. ??? Reporter: A music video for black matters U.S. Rallies against police brutality. Denunciations of Hillary Clinton. Even self-defense classes run by a group called black fist. All part of a sophisticated campaign targeting America's black communities run out of this building in St. Petersburg, Russia, according to congressional investigators. The strategy appears to be a mix of suppressing votes, stoking fear and doing all they can to help the preferred candidate in Donald Trump. Black matters U.S. Reporter: Investigators say it was no accident they created somebody accounts for a Gupta sounded like the legitimate black lives matter group. I don't think it's fair. Reporter: The St. Louis rapper who wrote the music for the black matters U.S. Video says he got Instagram messages from people he didn't know asking him to write a song dealing with police brutality. I had no clue that it was Russian anything like that. Reporter: The young activist who helped organize this protest rally in Charlotte, north Carolina, last September says it was people at black matters U.S. Who got him to do it to his later regret. Definitely make black lives matter look bad and make the entire movement look bad. Who knows who else was hoodwinked really by the same group. Reporter: Another Russian group called black fist organized self-defense classes offering protection against the police. Five American fitness trainers were hired to run the classes. They paid me $320 for the month, four classes. Reporter: Taking advantage of people who care about the community. Right. It's very sneaky. It's very sneaky. Very underhanded. Reporter: Facebook and Twitter have taken down the feeds of the groups, black Matt matters U.S. And black fist and appears these people don't exist. What a strange story. We turn to Las Vegas and the reaction to a new ad for mgm

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