In bidding for a landmark property project near Beijing's Olympics stadium in 2006, Guo toppled Liu Zhihua, a former Beijing vice mayor, with a sex tape of Liu. The mainland magazine Caixin reported Guo obtained the sex tape with the help of Ma Jian, a former deputy minister with China's state security ministry who is now in jail.
Guo said in the interview that he submitted the sex tape of Liu to China's disciplinary watchdog, but he didn't specify how he got the tape.
His reappearance came just a day before Xiao Jianhua, a mainland billionaire believed to have ties to party elites, was reportedly captured by mainland security agents in Hong Kong.
Li was sentenced to four-and-a-half years in jail for insider trading and other offences in November. He and several other top executives at state-owned Founder were arrested in 2014 in the fallout of a spat with Guo over the board composition of the group's securities house.
But Guo said he and Li were only "puppets" and that their battle was part of a struggle between the powers behind them. He also accused Li of hiding and laundering money for leaders in the Politburo and its Standing Committee.
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Li is known to have ties to former presidential aide Ling Jihua, who is now behind bars for life for corruption. However, Guo said Ling and his wife Gu Liping were only "small backers" of Li.
Fu, who was once considered a rising star in the police force, was removed last August from his post at the party's Central Politics and Law Commission.
Guo also said his employees on the mainland had been seized by a special investigation team and interrogated using "inhumane" methods.
In March 2015, mainland media published investigative reports accusing Guo of conspiring with officials during his rise to riches, including former deputy spy chief Ma Jian, who came under investigation for corruption that January.
At the time, Guo rejected accusations that he went into hiding overseas from graft-busters after Ma's downfall, claiming he was in New York for medical treatment and would soon return to China to clear his name.
But since then, Guo's whereabouts have remained a mystery. He did not respond to a request for comment on Tuesday.