NEW YORK — An American citizen has pleaded guilty to helping run what has been described as the first known secret police station in the US on behalf of the Chinese government.

Prosecutors say Chen Jinping and his co-defendant Lu Jianwang opened and operated the station in Manhattan's Chinatown neighborhood in early 2022 on behalf of China's Ministry of Public Security (MPS).

At least 100 such stations have been reported worldwide across 53 countries, with rights groups accusing China of using the outposts to threaten and monitor Chinese nationals abroad.

But China has denied that they are police stations, saying they are "service stations" providing administrative services to nationals overseas.

The outpost, which occupied an entire floor above a ramen stall, did provide basic services like renewing Chinese citizens' driver licenses, but it also helped Beijing identify pro-democracy activists living in the US, say federal authorities.

Matthew Olsen, an assistant attorney general in the US Department of Justice, called the attempt to operate the undeclared overseas police station "a clear affront to American sovereignty and danger to our community that will not be tolerated".

The station was closed in the autumn of 2022 after the Federal Investigation Bureau launched an investigation.

But Chen and Lu destroyed text messages they exchanged with an MPS official when they learned of the probe, prosecutors said.

The men, who are both American citizens, were arrested in April last year.

On Wednesday, Chen, 60, pleaded guilty to conspiring to act as an agent for China, and faces up to five years in prison when he is sentenced next year.

Chen's acknowledgment of guilt is a "stark reminder of insidious efforts taken by the [Chinese] government to threaten, harass, and intimidate those who speak against their Communist Party," Robert Wells, an executive assistant director of the FBI's National Security Branch said in a statement.

Lu, 59, has pleaded not guilty and is awaiting trial. Prosecutors have accused him of harassing a purported Chinese fugitive to return to China and for helping to locate a pro-democracy activist in California on behalf of the Communist Party.

At the time of Chen's arrest, authorities said it marked the first time the US has brought criminal charges in relation to such police outposts.

Mr Olsen said US authorities would "continue to pursue anyone who attempts to aid the PRC's efforts to extend their repressive reach into the United States".

In September, Linda Sun, a former aide in the New York governor's office, was charged with using her position to serve Chinese government interests. She was said to have received benefits, including travel, in return.

Last year, 34 officers from the MPS were also charged with using fake social media accounts to harass Chinese dissidents in the US and spread official Chinese government propaganda. — BBC