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Donald Trump: Elizabeth Warren is a "racist"

Clinton vs Trump Analysis

Donald Trump asserted Monday that Massachusetts Sen. Elizabeth Warren is a "racist."

In a phone interview with NBC News, the presumptive GOP nominee said Warren faked her Native American heritage--an issue that came up during her 2012 Senate bid--and that as a result, she is "racist."

"She made up her heritage, which I think is racist. I think she's a racist, actually because what she did was very racist," Trump said in a phone interview.

Warren, who endorsed presumptive Democratic nominee Hillary Clinton earlier this month, made her first joint appearance with Clinton in Ohio Monday morning.

Trump has made a habit of referring to Warren as "Pocahontas," in another reference to the question about her Native American heritage. Warren, who's been one of Trump's harshest critics this spring, has clearly struck a nerve: he frequently attacks her on Twitter and in speeches and interviews.

Monday was no exception, with Trump also sending this tweet about Warren:

"She used the fact that she was Native American to advance her career," he told NBC. "Elizabeth Warren is a total fraud. I know it. Other people who work with her know it. Elizabeth Warren is a total fraud."