Transcript for Trump's former campaign chairman now accused of witness tampering

Next, this evening, a jud now weighing in tonight after a major development lastht evolving Paul mana fort. Specl counsel Robert Mueller is now the former trumpmpaign chairof witness tampering F while he was under hsearrest. Mueller now asking a Jo consider revoking manafort's bail and sending him to jail. ABC's chius coespondent erre Thomas tonight. Rr: He's been under house arrest months, but tonight, president trump's former campaigchairman, Paul fort, may sbeding to jail. Federal prosecutors now accuse him of witness tampering. Ecutors say manafort and a personved to be a former Russian intelligence officer contactetwo witnesses by phone D using encrypted text messages,rying to to lie about hisbying wk for ukrain politicians with ties laputin. One witness making thexplosive claim manafort to, quote,ub born ury. Manafortcharged with fraud andonlaundering. It's been nearly a year since I raided his hwas still B I've always found Paul manafo T a very decent maut I thought that was a very -- pretty tough stuff. To hup, perhaps his mily was there. I think that's pretty tough STUF Reporter: But over the ekend, a very difnt tone. The president fuming the FBI should havenformed him before the elect they were suspiciousf manafo's overseas connections tweeting, "Why wouldn't the FBI or department of justice hav told me they wereecretly investigating Paul manafort? Sh told me." The president' friend, Chris tie, former federal prosecutor, disag. I don't care what you were nning for, we're not telling you.we're not -- W not a private instigation firm to help you with vet your people who you employ in your campaign. Pierre Thomas wit us LIV in Washington tonight. And pi, Paul manafort has until fri to respond to the accuon of witness tamperi here, but bigger picture, with this neweat of possible jail timeinstead house arrest, marts facing mounting pressure here. Possible jail, fight this, or flip for Robert mur? Reporter:avid, there's no question that the Sal counsel is ramping up the prre on manafort. Buttonight, manafort is pushing back his spokesman releasing a statement that manafort is, quote, innocent, and nothing ou allegatio changes our defense. We will do our talking in court. David? Indicating the fight will go .

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