At a rally in Montana in July, Trump raised the stakes. "I will give you a million dollars to your favorite charity, paid for by Trump, if you take the test and it shows you're an Indian," he said.
"And let's see what she does, right? I have a feeling she will say 'no,' but we'll hold that for the debates!" Trump added.
Trump denied he ever made the promise in remarks to reporters Monday, but Warren reminded him in a tweet.
On Tuesday morning, Warren shot back at Trump's Twitter salvos in a pair of tweets.
Warren has long been accused by conservatives of leaning on her assertion of Native American heritage for political or professional gain. Trump has played up this criticism at his campaign-style rallies and on social media, and in his Tuesday morning tweet took his attack further, calling Warren "Pocahontas (the bad version)."
In a follow-up tweet, Trump directly accused Warren of exploiting her purported ancestry to get hired at Harvard Law School.
"Harvard called her "a person of color" (amazing con), and would not have taken her otherwise!" Trump said.
The Globe, however, published a report on Sept. 1 contradicting that claim. "Warren first listed her ethnicity as Native American nearly five months after she started her tenured position at Harvard and 2½ years after she was there as a visiting professor and first offered the job," the newspaper reported.
Trump wasn't the only one criticizing Warren's DNA test. A representative for the Cherokee Nation responded harshly to the whole exercise, saying in a statement: "A DNA test is useless to determine tribal citizenship."
"Current DNA tests do not even distinguish whether a person's ancestors were indigenous to North or South America. Sovereign tribal nations set their own legal requirements for citizenship, and while DNA tests can be used to determine lineage, such as paternity to an individual, it is not evidence for tribal affiliation. Using a DNA test to lay claim to any connection to the Cherokee Nation or any tribal nation, even vaguely, is inappropriate and wrong. It makes a mockery out of DNA tests and its legitimate uses while also dishonoring legitimate tribal governments and their citizens, whose ancestors are well documented and whose heritage is prove. Senator Warren is undermining tribal interests with her continued claims of tribal heritage."
In a third tweet on the subject, Trump thanked the Cherokee Nation "for revealing that Elizabeth Warren, sometimes referred to as Pocahontas, is a complete and total Fraud!"
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