The United States unsealed criminal charges on Thursday against seven Chinese nationals accused of waging a surveillance and harassment campaign against a US resident and his family, in a bid by the Chinese government to repatriate one of them back to China.

The eight-count indictment, unsealed in a US District Court in Brooklyn, New York, is the latest case by the Justice Department targeting China's apparent expatriation campaign, known as "Operation Fox Hunt".

The seven individuals charged are Quanzhong An, 55, of Roslyn, New York his daughter Guangyang An, 34, and five others still in China: Tian Peng, Chenghua Chen, Chunde Ming, Xuexin Hou, and Weidong Yuan.

The lead defendant, Quanzhong An, and his daughter were arrested on Thursday morning. The rest of the defendants remain at large. The United States does not have an extradition treaty with China.

According to the indictment, Quanzhong An is accused of working at the behest of China's Provincial Commission for Discipline Inspection to harass and intimidate a Chinese man and his son living in the United States. The man and his son are identified only as "John Doe-1 and John Doe-2."

As part of the plot, the defendants allegedly coerced a relative of the family to travel from China to the United States in a bid to convince John Doe-1 to return to the country.

At a meeting in a restaurant in Sept 2018, the relative explained to John Doe-2 that he had been forced to travel there by the government as part of a plan to repatriate the 100 most-wanted fugitives, the indictment said.

Other examples of harassment the family endured included a letter-writing campaign, with one letter warning that "coming back and turning yourself in is the only way out."

The Chinese government also filed a lawsuit against the father and son in a New York state court, claiming the father had stolen money from a Chinese employer and his son illegally profited from the scheme.

“The victims, in this case, sought to flee an authoritarian government, leaving behind their lives and family, for a better life here. That same government sent agents to the United States to harass, threaten, and forcibly return them to the People's Republic of China," said Michael Driscoll, the FBI's assistant director in charge in the New York office.

- Reuters