Transcript for Report: Trump under investigation for obstruction of justice

major new development in the Russia investigation. Special counsel Robert Mueller now investigating president trump for possible obstruction of justice. Our senior white house correspondent Cecilia Vega has all the latest on that. Good morning, Cecilia. It has caught the eye of the president already. Reporter: Yeah, George, the white house said they wouldn't be talking about the special counsel but the president himself is tweeting about it this morning, take a look. This is in reference to that "Washington post" story. Here's what he tweeted. They made up a phony collusion with the Russians story, found zero proof, so now they go for obstruction of justice on the phony story. Nice. So, the focus of the investigation had been the president's aides and their dealings with the Russians but "The Washington post" is now saying that special counsel Robert Mueller is looking into the president himself for possible obstruction of justice. Former FBI director James Comey just last week had testified that he told the president he was not under investigation. It seems that that change right after Comey was fired but, George, a key question right now, did the president ask Comey or others to back off of that Russian investigation? Yeah, this is going to become more than a he said/he said case and Comey will interview several individuals including the director of national intelligence, the director of the national security agency. Reporter: It looks like they're focused on Dan coats and whether the president asked him also to intervene and get the investigation to back off of the issue of Russia and former director of national -- NSA securitier adviser Mike Flynn. They call this a leak that's outrageous and illegal, George.

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