Sen. Elizabeth Warren (D-Mass.) was among those raising questions on Sunday over the firing of U.S. attorney Preet Bharara, accusing President Donald Trump of getting rid of Bharara for political reasons and warning him that he won't replace "real prosecutors with cronies without a massive fight."

The senator voiced her objections in a series of tweets Sunday morning:

.@realDonaldTrump talked a big game about getting corruption out of gov. But he wants a bunch of tame prosecutors who won’t investigate him. — Elizabeth Warren (@SenWarren) March 12, 2017

Weeks ago, @realDonaldTrump promised to keep Preet Bharara as the top federal prosecutor in Manhattan. Yesterday, Preet was fired. Why? — Elizabeth Warren (@SenWarren) March 12, 2017

Preet Bharara had authority over Trump Tower. @realDonaldTrump called him directly, breaching protocol. 24 hrs later he was asked to resign. — Elizabeth Warren (@SenWarren) March 12, 2017

GOP & Dems respect Preet Bharara as a fearless prosecutor who stands up to both parties & Wall Street. I guess that's why Trump fired him. — Elizabeth Warren (@SenWarren) March 12, 2017

.@realDonaldTrump fired acting AG Sally Yates – who refused to defend his #MuslimBan & had warned the WH about Flynn’s contact with Russia. — Elizabeth Warren (@SenWarren) March 12, 2017

.@realDonaldTrump wants people like AG Sessions – a loyalist who lied to the Senate about meeting with the Russians – in @TheJusticeDept. — Elizabeth Warren (@SenWarren) March 12, 2017

You can't fire the rule of law, @realDonaldTrump. You can't shut down ongoing investigations by career prosecutors. — Elizabeth Warren (@SenWarren) March 12, 2017

Newsflash, @realDonaldTrump: The Senate confirms US Attorneys. And you're not replacing real prosecutors with cronies w/out a massive fight. SCROLL TO CONTINUE WITH CONTENT Never Miss a Beat. Get our best delivered to your inbox.





— Elizabeth Warren (@SenWarren) March 12, 2017

Rep. Elijah Cummings (D-Md.) raised similar concerns Sunday during an interview with ABC's "This Week."

The Huffington Post reported:

"Just not very long ago, the president was saying that he was going to keep the U.S. attorney there in New York. And then, suddenly, he's, I guess, changed his mind. I'm just curious as to why that is," Cummings said. "And certainly, there's a lot of questions coming up as to whether Mr. Trump is—President Trump is concerned about the jurisdiction of this U.S. attorney and whether that might affect his future."

A group of ethics watchdogs sent Bharara a letter recently, asking him to investigate whether Trump's conflicts of interest: Democracy 21, Citizens for Responsibility and Ethics in Washington (CREW) and the Campaign Legal Center request that you undertake an investigation to determine if the Trump Organization LLC, the Trump Organization, Inc., and any related Trump businesses based in the Southern District of New York are receiving payments and financial benefits from foreign governments that benefit President Donald Trump and that do not comply with Article I, Section 9, Clause 8 of the United States Constitution, the “Foreign Emoluments Clause.”

Cummings confirmed Sunday that he believed there could be a connection between this call for an investigation and Trump's decision to get rid of Bharara, who is known as an aggressive prosecutor.

Watch below: