Several top Democrats - and at least one Republican - criticized President Trump for firing FBI Director James Comey.

Senator Bob Casey Jr. (D-Pennsylvania) compared Trump to President Richard Nixon in the way he terminated Comey in the midst of an investigation into Russian collusion.

"This is Nixonian. Deputy Attorney General Rod Rosenstein must immediately appoint a special counsel to continue the Trump/Russia investigation... This investigation must be independent and thorough in order to uphold our nation’s system of justice," Casey said in a statement.

This is Nixonian. Deputy AG Rod Rosenstein must immediately appoint a special prosecutor to continue the Trump/Russia investigation. — Senator Bob Casey (@SenBobCasey) May 9, 2017

Former 2016 vice presidential candidate Sen. Tim Kaine (D-Virginia) echoed Casey, firing off a series of tweets accusing Trump of firing Comey as a way to interfere in any investigation the FBI was conducting on his alleged Russian ties.

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Trump firing Comey shows how frightened the Admin is over Russia investigation — Senator Tim Kaine (@timkaine) May 9, 2017

Comey firing recommended by Sessions. I thought he had recused himself from Russia investigation! — Senator Tim Kaine (@timkaine) May 9, 2017

Comey firing part of a growing pattern by White House to cover-up the truth — Senator Tim Kaine (@timkaine) May 9, 2017

House Democratic Caucus Chairman Joseph Crowley (D-New York) called Trump's decision "extremely troubling."

"President Trump fired the man investigating him and his cohorts. I strongly support calls for the appointment of a special prosecutor," Crowley said.

Senator Chris Van Hollen of Maryland jabbed Trump over his reality show punchline, "You're Fired," saying that it "doesn't work" in politics.

The "you're fired" approach doesn’t work when you're President. @POTUS you're creating a crisis of confidence in our Justice Department. — Chris Van Hollen (@ChrisVanHollen) May 9, 2017

Congressman Carlos Curbelo, a Republican from South Florida, also questioned why Comey was fired:

Today’s extraordinary decision raises many questions all of which must be answered. My full statement here: https://t.co/smW3NE7JF8 https://t.co/YlUIH1VnxL — Rep. Carlos Curbelo (@RepCurbelo) May 10, 2017

Libertarian-leaning Rep. Justin Amash (R-Illinois) said he is studying whether it would be appropriate to call for an independent investigation into Russia's actions during the election, since Comey is no longer at his post.

My staff and I are reviewing legislation to establish an independent commission on Russia. The second paragraph of this letter is bizarre. https://t.co/wXeDtVIQiP — Justin Amash (@justinamash) May 9, 2017

Senator Richard Burr (R-North Carolina), the chairman of the intelligence committee, criticized Trump's firing of Comey:

New York's junior senator Kirsten Gillibrand also pointed to recent accusations of Russian collusion in her criticism of Comey's dismissal:

No more excuses: We need an independent special prosecutor to investigate the Trump Administration’s ties to Russia. — Kirsten Gillibrand (@SenGillibrand) May 9, 2017

Senate Minority Whip Richard Durbin (D-Illinois) released a lengthy statement on the matter:

My statement on the removal of @FBI Director James Comey pic.twitter.com/w8BpVateeq — Senator Dick Durbin (@SenatorDurbin) May 9, 2017

Senator Edward Markey (D-Massachusetts) said Comey's firing reminded him of the "Saturday Night Massacre" in the 1970s, when Nixon fired an independent prosecutor and accepted the resignation of a number of DOJ officials in the midst of the Watergate affair.

“President Trump’s firing of Director Comey sets a deeply alarming precedent as multiple investigations into possible Trump campaign or administration collusion with Russia remain ongoing, including an FBI investigation. This episode is disturbingly reminiscent of the Saturday Night Massacre during the Watergate scandal and the national turmoil that it caused. We are careening ever closer to a Constitutional crisis, and this development only underscores why we must appoint a special prosecutor to fully investigate any dealings the Trump campaign or administration had with Russia.”

House Minority Whip Steny Hoyer (D-Maryland), the second-highest ranking Democrat in the House, said Comey's firing is "deeply troubling and raises serious questions."

Senator Bill Nelson of Florida called for an independent investigation into Russian interference after hearing of Comey's firing.

Now it is more clear than ever that we need an independent commission to get to the truth of Russia’s interference with our election. — Bill Nelson (@SenBillNelson) May 9, 2017

Senator Maria Cantwell (D-Washington) joined calls for a special prosecutor into the Russian allegations due to Comey's firing.

Senate & House Judiciary Committees are going to continue investigating Trump's ties to Russia, but we need a special independent prosecutor — Sen. Maria Cantwell (@SenatorCantwell) May 10, 2017

What do you think of Comey's firing? Let us know in the comments and check out Charles Krauthammer's reaction HERE.

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