NEW YORK >> Two men were arrested Monday on charges that they helped establish a secret police station in New York City on behalf of the Chinese government, and about three dozen officers with China’s national police force were charged with using social media to harass dissidents inside the United States, authorities said Monday.

The cases, taken together, are part of a series of Justice Department prosecutions in recent years aimed at disrupting Chinese government efforts to locate in America pro-democracy activists and others who are openly critical of Beijing’s policies and to suppress their speech.

One of three cases announced Monday concerns a local branch of the Chinese Ministry of Public Security that had operated inside an office building in Manhattan’s Chinatown neighborhood before closing last fall amid an FBI investigation. The two men who were arrested were acting under the direction and control of a Chinese government official and deleted communication with that official from their phones after learning of the FBI’s probe, according to the Justice Department.

“This is a blatant violation of our national sovereignty,” Michael Driscoll, the head of New York’s FBI field office said at a news conference.

The men, identified as “Harry” Lu Jianwang, 61, of the Bronx, and Chen Jinping, 59, of Manhattan, both U.S. citizens, were arrested at their homes on Monday morning.

Attorney Deirdre Vondornum, representing Lu, declined to comment. An email message seeking comment was left with a lawyer for Chen.

At no point did the men register with the Justice Department as agents of a foreign government, U.S. law enforcement officials said. And though the secret police station did perform some basic services, such as helping Chinese citizens renew their Chinese driver’s licenses, it also served a more “sinister” function, including helping the Chinese government locate a pro-democracy activist of Chinese descent living in California, officials said.

“New York City is home to New York’s finest: the NYPD,” U.S. Attorney Breon Peace, the top federal prosecutor in Brooklyn, said at a news conference announcing the arrests. “We don’t need or want a secret police station in our great city.”

Justice Department officials in recent years have prioritized prosecutions of what’s known as “transnational repression,” in which foreign governments work to identify, intimidate and silence dissidents in the U.S.

A signature case concerning China was announced in 2020, when the Justice Department charged more than a half-dozen people with working on behalf of the Chinese government in a pressure campaign aimed at coercing a New Jersey man wanted by Beijing into returning to China to face charges.