(CNN) Rep. Eric Swalwell called acting Attorney General Matt Whitaker an "assassin" hired by President Donald Trump to "kill" special counsel Robert Mueller's investigation into Russian interference in the 2016 presidential election.

"We're not going to allow the President to just, you know, kill this Russia investigation by hiring an assassin like Matt Whitaker to come in and take it out," he told CNN's Wolf Blitzer on "The Situation Room" Monday when speaking about House Democrats' plans for investigations in the coming Congress.

When pressed by Blitzer on what he meant by "assassin," Swalwell accused Whitaker of being hired because he has already come to a conclusion on the Mueller investigation.

"Whitaker was hired because of his views on the investigation. He's prejudged the investigation," the California Democrat said.

Swalwell, who sits on the House Intelligence and Judiciary committees, said one of his committees would ensure their first move is to protect Mueller with their new majority.

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