The recent departure of anti-corruption czar Wang Qishan from China's Politburo standing committee is an indication of how seriously the ruling Chinese Communist Party is taking threats by an exiled billionaire to reveal documents backing up his claims of corruption at the highest levels, analysts said.
Guo, who also goes by the name Miles Kwok, applied for political asylum in the United States earlier this month after China issued a "red notice" via Interpol for his arrest in April, alleging a series of criminal offenses.
Guo has aired a number of salacious allegations via his Twitter account, and has blasted the administration of President Xi Jinping as a small clique of mafia-like "kleptocrats."
Among the unsubstantiated allegations are claims that Wang Qishan, who once headed the party's Central Commission for Discipline Inspection (CCDI), is himself engaged in corruption.
Guo also went public on Oct. 6 with a document that he said proved the extent of Chinese espionage activities on U.S. soil, posing a threat "100 or 1,000 times" greater than that posed by major terror attacks.
His claims are a huge blow to the president's image, regardless of whether they are substantiated, and to the reputation of the ruling party in general, analysts say.
Guo told RFA in an Oct. 25 interview that his claims are "even bigger" than those already revealed in U.S. media reports.
U.S.-based political analyst and cultural scholar Wu Zuolai said Guo's claims have succeeded in weakening what had been a "cast-iron alliance" between the president and his right-hand man.
"Xi Jinping and Wang Qishan had previously been a cast-iron alliance, but then Xi started to go in for this cult of personality, and a crack began to appear," Wu told RFA. "Guo Wengui made another crack in the relationship ... after which Xi distanced himself from the situation for a long time."
"After all, Wang Qishan was hugely important to Xi, and he did everything he could to protect his public image. But when push came to shove, Wang Qishan didn't make it into the core leadership team," Wu said.
Wu said he believes Xi finally squeezed Wang out under pressure from party elders at a key meeting before the 19th Party Congress earlier this month.
Former top Communist Party aide Bao Tong called for a full investigation into Guo's allegations against Wang.
"The first thing [incoming CCDI chief Zhao Leji should do] is to give the world some kind of account of the Wang Qishan incident," Bao told RFA. "If Wang Qishan is genuinely clean, then we would all know about it. This is a member of the revolutionary proletariat and a loyal communist."
"Sweeping this under the rug probably isn't an option."
Bao said Xi's campaign against high-ranking "tigers" and low-ranking "flies" has never amounted to a genuine anti-corruption operation.
"It is a totally different thing to anti-corruption," he said. "There are clearly countless tigers in this forest, so even if you kill 100 of them, there are still 1,000 left alive, and 10,000 more who are yet to be born."
"The only way to fight corruption is to do away entirely with the system that creates and protects it," Bao said.
State media reported on Thursday that three former top officials netted in the anti-corruption campaign in recent years "bribed" party members to vote a certain way at party congresses in 2007 and 2012.
Former security czar Zhou Yongkang and Ling Jihua, an ally of former president Hu Jintao, are currently serving prison terms connected to bribery, abuse of power, and illegally obtaining or disclosing state secrets.
Also accused is the more recently fallen former Chongqing party chief Sun Zhengcai, who is under investigation for corruption.
The three officials' past abuse of the voting system prompted the party to abandon the system of voting in favor of a "consultative" mechanism for choosing leadership during this week's 19th congress, state news agency Xinhua reported.
Xi's re-election as general secretary of the party was decided at the 19th Party Congress earlier this month by "unanimous vote," state media have reported, without detailing what such a process entails.
Rather than allowing a vote at the Party Congress, Xi spoke personally to 57 senior leaders and retired leaders "to seek their suggestions" between April and June this year, Xinhua said.
Reported by C.K. and Qiao Long for RFA's Mandarin Service, and by Ho Shan and Ma Lap-hak for the Cantonese Service. Translated and edited by Luisetta Mudie.