Washington (CNN) Rep. Denny Heck said Wednesday that recent indictments and sentencing memos show "the walls are closing in and this is the beginning of the end for the Trump administration."

"In light of what happened today," the Washington state Democrat told Erin Burnett on CNN's "Erin Burnett OutFront," "in light of all the events of the last couple of weeks and all the sentencing memos that have been filed now -- 36 indictments, three prison terms and the like -- I'm prepared to say something I've never said: The writing's on the wall, the walls are closing in and this is the beginning of the end for the Trump administration."

Heck, a member of the House Intelligence Committee, said special counsel Robert Mueller's investigation into possible collusion between Russian operatives and Trump associates during the 2016 presidential campaign and transition is "getting closer and closer."

Earlier Wednesday, President Donald Trump's former longtime attorney and fixer, Michael Cohen, was sentenced to three years in prison for crimes including campaign finance violations and tax evasion. Cohen implicated the President in August when he pleaded guilty in federal court and said that "in coordination and at the direction of a candidate for federal office," he had kept information that would have harmed Trump from becoming public during the campaign.

"They now have the President as an unindicted co-conspirator for campaign finance laws, breaking campaign finance laws," Heck told CNN.

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