U.S. President Donald Trump forced out the country's top law enforcement officer on Wednesday, a move Democrats warned could be a prelude to stopping the special counsel investigation.

Attorney General Jeff Sessions, in a resignation letter to Trump, said he was stepping down at the president's "request," suggesting he'd been pushed out of a job he'd refused to leave despite enduring a steady onslaught of presidential humiliations and insults over his recusal from the probe of Russian meddling in the 2016 presidential election.

Trump, in a pair of tweets, said the attorney general's chief of staff, Matthew Whitaker, would take over as the Justice Department's acting head; thanked Sessions, whom he once called his "embattled attorney general"; and said a permanent replacement would be named later.

The firing of Sessions, 71, a former Republican senator from Alabama and an early supporter of and adviser to Trump's 2016 presidential campaign, fueled Democratic fears that Trump may be maneuvering to shut down special counsel Robert Mueller's Russia investigation.

Congressional probe urged

Rep. Elijah Cummings of Maryland, the top Democrat on the House oversight committee and a frequent Trump critic, urged Congress to investigate "the real reason" for the attorney general's "termination."

Cummings, in light of Whitaker's past vocal criticism of the Russia probe, also pushed Congress to "confirm" that Whitaker will recuse himself from overseeing the Russia investigation.

At a testy White House press conference earlier Wednesday, Trump said he could end the Mueller investigation "right now," but "I stay away from it ... I let it just go on."

Other Democratic leaders also urged Whitaker to give up oversight of the investigation.

"Given his previous comments advocating defunding and imposing limitations on the Mueller investigation, Mr. Whitaker should recuse himself from its oversight for the duration of his time as acting attorney general," Senate Minority Leader Chuck Schumer, a New York Democrat, tweeted.

House Democratic leader Nancy Pelosi of California fired off a similar tweet: "Given his record of threats to undermine & weaken the Russia investigation, Matthew Whitaker should recuse himself from any involvement in Mueller's investigation. Congress must take immediate action to protect the rule of law and integrity of the investigation.

•Excerpted from a VOA report.

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