A retired New York Police Department sergeant is one of three defendants convicted of acting and conspiring to act in the United States as illegal agents of the People's Republic of China, officials said Tuesday.

Defendants Michael McMahon, Zhu Yong and Zheng Congying were found guilty by a federal jury in Brooklyn on June 20. All three men faced multiple counts in a superseding indictment that alleged they were working for the People's Republic of China to harass, stalk and coerce certain United States residents to return to China as part of a "global and extralegal repatriation effort known as 'Operation Fox Hunt,'" according to a news release by the Eastern District of New York. McMahon and Yong were knowingly working with officials from the People's Republic of China, officials said. 

McMahon, 55, the former sergeant, was convicted of acting as an illegal agent of the People's Republic of China, conspiracy to commit interstate stalking and interstate stalking. He faces up to 20 years in prison. 

Yong, also known as "Jason Zhu," 66, was convicted of conspiracy to act as an illegal agent of the People's Republic of China, acting as an illegal agent of the country, conspiracy to commit interstate stalking, and interstate stalking. He faces up to 25 years in prison. 

Zheng, 27, who left a threatening note at the residence of someone targeted by the stalking campaign, was convicted of conspiracy to commit interstate stalking and interstate stalking. He faces up to 10 years in prison. 

The trio will be sentenced at a future date. 

Three other defendants have previously pled guilty for their roles in the harassment and intimidation campaign. 

The trial found that the defendants worked between 2016 and 2019 to threaten, harass, surveil and intimidate a man and woman, known only as John Doe #1 and Jane Doe #1, with the goal of convincing the couple and their family to return to the People's Republic of China. Yong hired McMahon, who was retired from the NYPD and was working as a private investigator. 

McMahon obtained detailed information about John Doe #1 and his family and shared it with Zhu and a People's Republic of China police officer. He also conducted surveillance outside the New Jersey home of John Doe #1's sister-in-law and provided further information about what he observed there. The operation was supervised and directed by several People's Republic of China officials.

Two of those officials, identified as police officer Hu Ji with the Wuhan Public Security Bureau and Tu Lan, a prosecutor within the Wuhan region, later transported John Doe #1's 82-year-old father from the People's Republic of China to the sister-in-law's home to convince John Doe #1 to return to the country. While in the man was in the United States, his daughter was threatened with imprisonment in the People's Republic of China, the trial found. 

McMahon followed John Doe #1 from the meeting with his father at the New Jersey home back to his own house. This gave him John Doe #1's address, which had not been previously known. He gave that information to operatives from the People's Republic of China. 

Zheng visited the New Jersey residence of John and Jane Doe #1 and attempted to force the door of the residence open before leaving a note that read "If you are willing to go back to the mainland and spend 10 years in prison, your wife and children will be all right. That's the end of this matter!" 

In:
• NYPD
• China
• New York

Kerry Breen

Kerry Breen is a news editor and reporter for CBS News. Her reporting focuses on current events, breaking news and substance use.