WASHINGTON, July 22 (Reuters) - The U.S. Justice Department on Thursday accused a prosecutor employed by the Chinese government of traveling to the United States to direct a harassment campaign aimed at bullying Chinese residents to return home to face criminal charges. Tu Lan, 50, who served as a prosecutor with the Hanyang People’s Procuratorate, is the latest defendant in a sprawling investigation that has led to charges against nine people accused of participating in a covert operation to conduct surveillance on, harass, stalk and coerce Chinese people living in the United States to return to China through a repatriation effort known as "Operation Fox Hunt." Tu Lan and another defendant, Zhai Yongqiang, 46, are the latest to be charged in a superseding indictment returned by a federal grand jury in New York. Lan is also accused of ordering another co-conspirator to destroy evidence and obstruct the investigation. The name of the ninth defendant remains under seal. When the case was announced in October, the Justice Department said it was "the first case of its kind" because it involves the efforts of a foreign power to conduct unilateral activity on U.S. soil. The allegations in the case read like a spy novel. They involve charges against an American private investigator and former New York City police sergeant, Michael McMahon, whom prosecutors allege was hired to surveil one of the operation"s targets, referred to in the indictment only as "John Doe #1." Three of the defendants who were arrested, including McMahon, have pleaded not guilty. Lawrence Lustberg, McMahon"s attorney, told Reuters his client had actually been "deceived and duped" and "never knew that, in his actions as a hired private investigator, he was acting in any way on behalf of the Chinese government." The indictment alleges "the co-conspirators planned a specific rendition operation to stalk and repatriate John Doe #1 through psychological coercion." This included a plan in April 2017 to bring the victim"s elderly father to the United States from China to convey the message that if he failed to return, his family would suffer "serious harm." The indictment says Tu Lan flew from China to New Jersey to help oversee the operation, where she later met with other co-conspirators and directed them to spy on one of John Doe #1"s relatives. She later returned to China, where prosecutors say she continued to oversee the effort. The plot ultimately failed, and she and others ordered that the father be returned to China, while she also allegedly ordered a co-conspirator to "delete all the chat content" about their plans.