WASHINGTON, United States (AFP) — US President Donald Trump on Tuesday fired his FBI director James Comey, the man who leads the agency charged with investigating his campaign’s ties with Russia — a move that sent shockwaves through Washington.

The surprise dismissal of Comey, who played a controversial role in the 2016 presidential election, came as he was leading a probe into whether Trump’s aides colluded with Moscow to sway the vote.

“The president has accepted the recommendation of the attorney general and the deputy attorney general regarding the dismissal of the director of the Federal Bureau of Investigation,” White House spokesman Sean Spicer told reporters.

A search for a new FBI director was to begin “immediately,” the White House said in a statement.

In a letter, Trump told Comey: “You are hereby terminated and removed from office, effective immediately.”

“While I greatly appreciate you informing me, on three separate occasions, that I am not under investigation, I nevertheless concur with the judgment of the Department of Justice that you are not able to effectively lead the Bureau.”

“It is essential that we find new leadership for the FBI that restores public trust and confidence in its vital law enforcement mission,” Trump said.

FBI directors are appointed for a single 10-year term. The 56-year-old Comey, who is popular among rank-and-file agents, was appointed four years ago.

Democrat Hillary Clinton accused Comey of trashing her chances of becoming president by revealing an renewed investigation into her email use.

His dismissal will raise questions about Trump’s motives.

It will also prompt parallels with Richard Nixon’s decision to unceremoniously fire his attorney general, an event that plunged his presidency deeper into crisis.

In March, Comey revealed that the agency is investigating Russian interference in last year’s presidential election and notably Moscow’s possible collusion with President Donald Trump’s campaign.

During testimony to Congress, he also flatly rejected Trump’s explosive claim that he was wiretapped by his predecessor Barack Obama.

The explosive testimony in the House Intelligence Committee — the first public hearing into both controversies — came as Trump sought to steer the news focus by calling the Russia issue, which has been a cloud over his November victory, “fake news.”

Republicans pointed to Comey’s recent misstatement to Congress about Clinton forwarding emails to an aide as a possible reason for his dismissal.

“Given the recent controversies surrounding the director, I believe a fresh start will serve the FBI and the nation well,” said Senator Lindsey Graham.

“I encourage the president to select the most qualified professional available who will serve our nation’s interests.”

Democrats — already angry that Congressional inquiries have been hamstrung by Republicans’ willingness to defend Trump — worried that the FBI’s investigation may also be in jeopardy

“Congressional Republicans cannot possibly disagree now: the only fix to this mess is an independent commission with subpoena power,” said Brian Fallon, a former Justice Department and Hillary Clinton spokesman.