President Donald Trump on Thursday night tweeted out an edited video showing Nancy Pelosi stumbling over her words, escalating the personal attacks he has made against the Democratic House speaker.

The video, apparently from a segment on Fox Business' "Lou Dobbs Tonight," features portions of a 20-minute news conference Pelosi held Thursday in a montage that lasts about 30 seconds. It shows her tripping over her words. At one point in the video, a moment is repeated several times.

“PELOSI STAMMERS THROUGH NEWS CONFERENCE” pic.twitter.com/1OyCyqRTuk — Donald J. Trump (@realDonaldTrump) May 24, 2019

Trump tweeted the video hours after he called Pelosi "crazy" and said, "She is not the same person. She has lost it." It comes a day after Trump cut short a meeting with Pelosi and Senate Minority Leader Chuck Schumer because he is frustrated with congressional efforts to investigate his administration.

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Pelosi’s press secretary did not return a phone call seeking comment Thursday night.

The speaker's daughter, Christine Pelosi, however, offered some choice words for Trump, tweeting Friday morning that the president was having a "Trumper tantrum" and was spreading a "doctored video against Madam Speaker."

About that Trumper tantrum and doctored video against Madam Speaker:



As in 2016, he wants a fight between himself and a single Democrat — but this is a fight between Trump and the evidence against him.



So we must #followthefacts and discuss them not him - do not lose focus! — Christine Pelosi (@sfpelosi) May 24, 2019

But Rudy Giuliani, one of Trump's lawyers, doubled down on the video Friday morning, tweeting in part that it was a "caricature exaggerating her already halting speech pattern."

Nancy Pelosi wants an apology for a caricature exaggerating her already halting speech pattern. First she should withdraw her charge which hurts our entire nation when she says the President needs an “intervention. “People who live in a glass house shouldn’t throw stones.” — Rudy Giuliani (@RudyGiuliani) May 24, 2019

Video on C-SPAN of Pelosi’s full weekly legislative briefing with reporters Thursday shows Pelosi making the same stumbles seen in the clip tweeted by the president. The briefing lasted about 20 minutes.

The tweet by the president comes after The Washington Post published a story about a different video circulating on social media of Pelosi at a Center for American Progress event. The video was slowed down to make it sound as if she was slurring her words, The Post reported.

In a tweet Thursday reacting to the Post story, Christine Pelosi said, "Republicans and their conservative allies have been pumping this despicable fake meme for years!"

About that Trumper tantrum and doctored video against Madam Speaker:



As in 2016, he wants a fight between himself and a single Democrat — but this is a fight between Trump and the evidence against him.



So we must #followthefacts and discuss them not him - do not lose focus! — Christine Pelosi (@sfpelosi) May 24, 2019

Hany Farid, a computer science professor and digital forensics expert at the University of California, Berkeley, told the Post of the distorted Center for American Progress video: “There is no question that the video has been slowed to alter Pelosi’s voice."

But he said he believed the video Trump tweeted Thursday had not been slowed down.

"Unlike the video referred to in The Washington Post article, I don’t believe that this video montage was slowed down. This montage, however, is highly deceptive as it compiles in rapid succession relatively small verbal stumbles in an attempt to portray Speaker Pelosi as stumbling through her press conference," Farid told NBC News.

"The original C-SPAN video clearly shows that this montage that the president tweeted is not an accurate depiction of her press conference," Farid said.

Drew Hammill, Pelosi’s deputy chief of staff, on Twitter called the video that Trump tweeted Thursday night "doctored" and referred to the Post article. Hammill said in an email Friday he was referring to the editing of the video and was not suggesting it was altered.

Christine Pelosi tweeted about the video Trump posted Thursday night: "Fake video altered for speed."

A spokesperson for the Fox Business Network, on which "Lou Dobbs Tonight" airs, said in a statement that "The FOX Business segment featuring clips from Speaker Pelosi's speech today did not slow down any aspect of her address."

Pelosi has also taken swipes at Trump. "When the 'extremely stable genius' starts acting more presidential, I'll be happy to work with him on infrastructure, trade and other issues," Pelosi tweeted earlier Thursday.

The reference is to comments Trump has made about being a "very stable genius."

And before the infrastructure meeting collapsed Wednesday, Pelosi accused Trump of engaging "in a cover-up."

The president denied the allegation. “I don’t do cover-ups,” he said from the Rose Garden.