Interpol has issued a "red notice" seeking the arrest of Guo Wengui, a mainland billionaire who has threatened to expose corruption at the highest levels of the ruling Communist Party.
Foreign ministry spokesman Lu Kang gave no details about the alleged crimes of Guo, pictured, when announcing the Interpol notice.
The real estate tycoon disappeared from public view in 2014 but resurfaced in recent months, claiming in two interviews with overseas Chinese media and a stream of Twitter posts that he held damning information about party elites.
His case has been closely followed by Chinese political watchers, who say his leaks could be potentially damaging as internal factions jostle for power in the months leading up to the 19th Party Congress this fall, when a new generation of party leaders will be chosen.
Guo, who is believed to be in London, has been linked to Ma Jian, a former deputy head of China's intelligence service who was charged with corruption in February.
Guo dismissed the notice as an empty threat from Beijing. "It's all lies, all threats. It shows they are scared of me leaking explosive information," he said. "Don't worry, this is a good thing."
Guo was not listed on Interpol's website.