Democratic Sen. Elizabeth Warren, who is widely speculated to be positioning herself for a 2020 presidential bid, tore into President Donald Trump on Twitter for his decision to abruptly terminate Preet Bharara, the famed U.S. attorney for the Southern District of New York.

Bharara is a "fearless prosecutor who stands up to both parties & Wall Street" and "had authority over Trump Tower," Warren wrote on Sunday.

"I guess that's why Trump fired him," Warren added.

Warren pointed to a pattern of Trump firing people who questioned the legality of some of his decisions.

"You can't shut down ongoing investigations by career prosecutors," Warren tweeted. "Newsflash, @realDonaldTrump. The Senate confirms U.S. attorneys. And you're not replacing real prosecutors with cronies without a massive fight."

Warren's tweets mirrored the suspicions of another lawmaker, Rep. Elijah Cummings, who said Sunday morning he believed Trump was trying to destroy potential threats to his power. 

In a slightly cryptic tweet on Sunday, Bharara appeared to confirm suspicions there was something untoward about his firing.

"By the way, now I know what the Moreland Commission must have felt like," Bharara posted.

The Moreland Commission was an investigation into corruption in Albany, the state capital of New York, created by Gov. Andrew Cuomo in July 2013. Cuomo later shut down the commission amid reports he had "deeply compromised" its work through self-serving interference.