Donald Trump told NBC’s Lester Holt he’d have to “report back” with evidence to bolster the inaccurate and unsupported claims he made about Hillary Clinton in a speech Wednesday.

In an interview that aired Thursday, Holt challenged Trump to back up the claim he made that Clinton’s private email server had been hacked. Trump responded, “I think I read that” and “I heard it,” but admitted that he would have to “report back” with the exact source. He finally concluded that “I don’t know if certainty. I — probably she was hacked.”

HOLT: But is there any evidence that it was hacked other than routine fishing– TRUMP: I think I read that — HOLT: –attacks? DONALD TRUMP:–and I heard it, and somebody— HOLT: Where? TRUMP: –that also gave me that information. I will report back to you. I’ll give it to you. HOLT: But you just said it with such certainty yesterday. TRUMP:–I don’t know if certainty. I– probably she was hacked. You know, a lot — you can be hacked and not know it, but she probably was hacked. The fact is she should not have it, she should not have had a personal server.

Holt also pushed Trump on his assertion that Clinton “slept soundly in her sleep” while the attack in Benghazi, Libya occurred. Again, after a brief exchange with Holt, Trump conceded that she may not have been literally asleep, as he said both during his speech Wednesday and at an April speech on foreign policy.

TRUMP: Were you there — HOLT: That Ambassador Stevens was asking – TRUMP: were they there? Were you with her – HOLT: — she has testified before the committee that she wasn’t asleep. It happened during the daytime. There’s no evidence — TRUMP: I – all during the day and the during — it was going on for a long period of time. HOLT: But I guess what I’m asking, what do you – TRUMP: No, excuse me — it was going on for — HOLT: –it on? TRUMP: — a long period of time. And she was asleep at the wheel. Whether she was sleeping or not, who knows if she was sleeping — HOLT: Well, you said — TRUMP: –she might have been — HOLT :–she was sleeping. TRUMP: –sleeping. She might have been sleeping. Why? Because she put out a tweet? Somebody said she put out a tweet, therefore she wasn’t sleeping. Nobody else could put out a tweet? So — HOLT: So you stand by — TRUMP:– I don’t know — HOLT: –what you said? TRUMP: –I can tell you this. Whether she was sleeping or not, and she might have been sleeping, it was a disaster. It was a horrific disaster, and it was on her watch.

The attack happened during the afternoon eastern time, and FactCheck.org has said that there is no evidence to support Trump’s claim that Clinton went home and slept rather than respond to the attacks.

At another point in the interview Trump admitted that he would possibly take money from Wall Street, despite attacking Clinton for doing the same. “I don’t know. I mean, we’ll have to see who comes up,” he said.

Video and transcripts courtesy of NBC News.

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