Transcript for House Russia probe eyes longtime Trump bodyguard

We're following several stories out of Washington. Senate majority leader Mitch Mcconnell trying to reach consensus on Obamacare repeal hoping for a vote but few signs he's picking up the support he needs. House set to vote on two new bills and president trump will hold his first meeting with south Korean's president and how to deal with North Korea at the top of the agenda. New developments in the Russell investigation. One of president trump's closest personal aides is now facing questions. Our senior white house correspondent Cecilia Vega here with the details. Good morning, Cecilia. Reporter: Good morning. This probe is widening. Investigators are now looking at the president's inner circle. As you said one of the people they now want to talk to is one of the president's closest aides. He is president trump's longtime former bodyguard turned top white house aide. Such close ties he has an office right next to the oval office. And this morning, ABC news has learned Keith Schiller is now on the list of witnesses that house intelligence committee investigators want to talk to as part of their probe into possible ties between team trump and the Russians. Schiller did not respond to a request for comment. But sources close to the investigation tell ABC news people on that witness list have been notified. Schillerh has known president trump for nearly two decades. A former New York City police officer who is now director of oval office operations, the president assigning him such tasks as hand delivering the letter to FBI headquarters that told former director James Comey he'd been fired. He is rarely heard from publicly. But he is nearly always by the president's side, known for being fiercely protective. During the campaign Schiller was seen hitting a protester outside trump tower. Stop it! Reporter: He was at the center of this now infamous moment. Excuse me, sit down. You are weren't called. Sit down. I have the right to ask the question. Reporter: After just a look from his boss, it was Schiller who ushered univision anchor Jorge Ramos out of that news conference. Don't touch me, sir. Don't touch me. You cannot touch me. Reporter: One white house official here tells me they're not surprised to learn Schiller's name was on this list, in fact, several white house officials here expect that their names could end up on this list too, George, as this Russia probe continues. Do we have any idea who those officials will be? Reporter: Well, George, we're learning a little bit more as this investigation moves forward. We know that investigators want to talk to, for example, the president's son-in-law Jared Kushner, we know that they want to talk to his longtime friend Roger stone. This is essentially a witness list, that's what this is and as this investigation moves forward, more names are being added to it. Expected to get wider. Thanks very much.

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