The United States has warned Beijing about Chinese agents it says are operating secretly in the US to pressure fugitives to return to China, The New York Times reported Sunday.

Citing unnamed US officials, the Times said the effort, part of Beijing's global manhunt dubbed Operation Fox Hunt, sought to repatriate fugitives wanted for corruption and other misdeeds and recover illicit funds.

In recent weeks, the US State Department issued a warning to Chinese officials to halt these activities.

The complaints come ahead of Chinese President Xi Jinping's state visit to Washington next month.

The newspaper said the agents, working not as spies but rather undercover for China's Ministry of Public Security, were most likely entering the country on tourism or trade visas.

Their strong-arm tactics include threats to family members, and have increased in recent months.

The State Department did not immediately respond to a request for comment.

More than 930 suspects around the world have been repatriated to China since last year under the program, the Times said, citing the Ministry of Public Security.

The fugitives sought under the program are believed to be prominent expatriates, some of whom are being sought for economic corruption or what Beijing considers political crimes.