WASHINGTON — President Donald Trump has fired the federal government’s top ethics official as well as the leader of the agency dedicated to protecting whistleblowers — the latest moves in the Republican president’s sweeping effort to shrink and reshape the government.

Hampton Dellinger filed a lawsuit Monday claiming he was illegally removed as the head of the Office of Special Counsel, which is responsible for protecting the federal workforce from illegal personnel actions, such as retaliation for whistleblowing. Also on Monday, the U.S. Office of Government Ethics posted on its website that Trump had removed its director, David Huitema.

The removal of Dellinger and Huitema, who were both confirmed last year by the Senate to serve five-year terms, comes as Trump is testing the limits of well-established civil service protections by moving to dismantle federal agencies and push out staffers.

The White House said Monday that recently confirmed Department of Veterans Affairs Secretary Doug Collins has been named the acting leader of both agencies.

Huitema said in an interview that he was notified over the weekend of his removal in an email that provided no explanation. Huitema said he was “extremely disappointed,” adding that he was committed to the mission of the office and its staff, “who represent the best of public service.”

Dellinger was fired in a Friday evening email from the White House personnel director. Dellinger noted in his lawsuit, filed in Washington federal court, that special counsels can be removed by the president “only for inefficiency, neglect of duty, or malfeasance in office.”

“The effort to remove me has no factual nor legal basis — none — which means it is illegal,” Dellinger said in an email. He’s seeking a court order finding that his termination was illegal and reinstating him as the special counsel.

The Office of Special Counsel investigates whistleblower claims of reprisal, can pursue disciplinary action against employees who punish whistleblowers and provides a channel for employees to disclose government wrongdoing. In his lawsuit, Dellinger said the office’s “ability to protect the civil service and investigate alleged misconduct is needed now more than ever,” noting the “unprecedented” number of firings without cause of federal employees with civil service protections in recent