Secretary of State Marco Rubio and his aides shut down a State Department office Wednesday that tracks and counters global disinformation from foreign actors, including the governments of China, Russia and Iran, U.S. officials said.

The closing of the office, the Counter Foreign Information Manipulation and Interference Hub, had been in the works for weeks. Rubio put all 40 or so of its employees on paid leave Wednesday morning, the first step in firing them this spring. The State Department fired about 80 contractors working for the office in March and cut almost all contracts related to its work.

The office had been tracking disinformation campaigns by rival powers of the United States, as well as terrorist groups, and publishing reports on them. Some Republican lawmakers in recent years have accused federal employees and nongovernment experts working on tracking disinformation of trying to stifle the views of right-wing political groups around the world and trying to coordinate with social media companies to do so. Russian disinformation often circulates in far-right online channels.

Rubio released a statement before noon Wednesday announcing the closure, saying that the office and its precursor in the Biden administration had “spent millions of dollars to actively silence and censor the voices of Americans they were supposed to be serving.” Rubio did not present any evidence to support the claim.

James Rubin, a former State Department official who ran the precursor to the office in the Biden administration, pushed back on the move to shutter the operation.

“This amounts to a form of unilateral disarmament in the information warfare Russia and China are conducting all over the world,” he said Wednesday.

He said that on his watch, “no efforts were made inside the United States — only international. All of our efforts were focused on Russian and Chinese operations in Latin America, Europe and Africa.”

The office now falls under the authority of Darren Beattie, a political appointee who is the senior official acting as the undersecretary for public diplomacy. Beattie was organizing the firings, said two U.S. officials who spoke on the condition of anonymity to candidly discuss actions by senior aides to President Donald Trump.

Beattie was fired from a job as a White House speechwriter during the first Trump administration after CNN published a report saying he had given a speech to a group of White nationalists. He has made controversial social media posts on issues of race, including one that said “competent White men must be in charge if you want things to work.”

After starting his job at the State Department, Beattie gained access to the email accounts of current and former employees who had worked on countering disinformation, the two U.S. officials said. He has looked through them to find evidence of censorship of conservative ideas, they said.