Story highlights Scott Brown spoke Monday on behalf of Trump

He ran against Warren in 2012

(CNN) Former Sen. Scott Brown on Monday stepped into the attack dog role for Donald Trump, saying his former Senate opponent Elizabeth Warren should "take a DNA test" if she wants to prove her Native American heritage.

"She's not Native American, she's not 1/32nd, she has no Native American background, except for what her family told her," Brown told reporters on a conference call hosted by the Republican National Committee, hours after Hillary Clinton and Warren appeared at an event together. "The easy answer, as you all know, is that Harvard and Penn can release those records, she can authorize the release of those records, she can take a DNA test, she can release the records herself. There's never been any effort," Brown said.

Warren responded on Tuesday telling the hosts of ABC's "The View" that the comments were aimed at bullying her "into shutting up."

"What this is really about is can they bully me into shutting up?" she said. "Can they be nasty enough and ugly enough and throw enough in my direction that I will say 'oh' and just go back into the shadows? And the answer is nope, not happening."

Warren and Clinton appeared at a campaign event together earlier in the day, a large part of which was spent slamming Trump, the presumptive Republican nominee.

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