Washington (CNN) Democratic Sen. Richard Blumenthal said President Donald Trump's firing of Attorney General Jeff Sessions is a "break the glass moment."

Trump fired Sessions on Wednesday and announced that Matthew Whitaker, who was Sessions' chief of staff, will take over as acting attorney general.

"It's a break the glass moment. Our democracy is under attack because the President has completely broken the norms of the normal succession process," the senator from Connecticut told CNN's Kate Bolduan on "Erin Burnett OutFront."

"It's a kind of slow-motion 'Saturday Night Massacre,' as occurred under President Nixon."

The "Saturday Night Massacre" was one of the most dramatic events in the Watergate scandal in the 1970s, which led to the resignation of President Richard Nixon. Nixon was refusing to comply with orders to release recordings of White House conversations, and then had Watergate special prosecutor Archibald Cox fired. Attorney General Elliot Richardson and his deputy William Ruckelshaus resigned rather than comply with Nixon's order. Cox was eventually fired by the US solicitor general.

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