Trump Foundation Paid Activist Filmmaker James O'Keefe

Conservative undercover journalist James O'Keefe
Chip Somodevilla | Getty Images
Conservative undercover journalist James O'Keefe

At the third presidential debate, Donald Trump invoked a video that says supporters of Hillary Clinton were paid to incite violence at one of his rallies in Chicago. It was an attack thread to emphasize that her campaign was "sleazy."

But what Trump didn't say is that he has paid the filmmaker who he says uncovered the story.

The video, which was just released earlier this week and made by conservative activist James O'Keefe of Project Veritas, was paid $10,000 by the Trump Foundation in May of 2015 - one month before Trump's announcement of candidacy.

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"They hired people. They paid them $1,500, and they're on tape saying be violent, cause fights, do bad things," Trump said on the debate stage Wednesday night, referencing the video by O'Keefe.

NBC News has not corroborated the video.

The payment was first reported by Think Progress and was listed in a compilation of donations the Trump Foundation gave to the Washington Post.

"I was wondering what happened with my rally in Chicago and other rallies where we had such violence. She's the one and Obama that caused the violence," Trump said at the debate.

O'Keefe has produced numerous videos that have attempted to take down members of the media, Democrats or progressives. He led the videos during the 2008 election of progressive group ACORN and attempted to show that Planned Parenthood sold aborted fetuses.

Breitbart is the platform where O'Keefe's videos are posted. The former head of Breitbart, Steve Bannon, is the CEO of Trump's campaign.

An original version of this story said O'Keefe was the producer of a video about Agriculture Department employee Shirley Sherrod. He was not.