Washington(CNN) Sen. Elizabeth Warren said she believes that the Democratic National Committee was "rigged" in favor of former Democratic presidential nominee Hillary Clinton during the 2016 primary.

Asked Thursday by CNN's Jake Tapper whether she believes that the Democratic campaign organization was tipped in favor of Clinton over her primary opponent, independent Vermont Sen. Bernie Sanders, Warren responded without hesitation: "Yes."

"We learned today from the former Democratic National Committee Chairwoman Donna Brazile that the Clinton campaign, in her view, did rig the presidential nominating process by entering into an agreement to control day-to-day operations at the DNC," Tapper said, continuing on to describe specific arms of the DNC the Clinton camp had a say over, including strategy and staffing, noting that the agreement was "entered into in August of 2015," months before Clinton won the nomination.

Warren called that "a real problem."

"But what we've got to do as Democrats now is we've got to hold this party accountable," Warren said.

The Massachusetts Democrat is seen as a possible presidential contender in 2020 and beyond.

Tapper then asked, "Do you agree with the notion that it was rigged?" And Warren responded simply: "Yes."

President Donald Trump referred to Warren's comments on Friday morning, calling her "Pocahontas" -- his regular moniker for the Massachusetts senator, a reference to her claims of having Native American ancestry -- and called for the FBI and Justice Department to look into Brazile's claims.

The question came up after Brazile's book excerpts were released this week, detailing the DNC's financial turmoil during the election and the role that the Clinton campaign played in aiding it financially.

"Debbie (Wasserman Schultz) was not a good manager," Brazile wrote in excerpts released in Politico on Thursday. "She hadn't been very interested in controlling the party -- she let Clinton's headquarters in Brooklyn do as it desired so she didn't have to inform the party officers how bad the situation was."