Beijing trains sights on tycoon who mocked Xi's virus response

The Commission for Discipline Inspection in Beijing said in a statement that Mr Ren was being investigated for "serious violation of law and discipline”. This is a charge typically directed at the Communist Party's critics and usually results in a prison sentence.

Mr Ren is the retired chairman of Huayuan Properties, a huge property developer. He is known in China as “the Cannon” for his outspoken views and rare challenges to the ruling Communist Party. He has tens of millions of followers on social media.

He disappeared last month after publishing an essay which accused Mr Xi of mishandling the health crisis. The essay referred to a "clown with no clothes on who was still determined to play emperor" in a reference to the Emperor's New Clothes, a classic Danish story about an emperor unfit for duty.

He was critical of a culture of flattery in Chinese politics, and referred to a February 23 meeting of 170,000 Party cadres and military personnel which heaped praised on Mr Xi.

Mr Ren was reprimanded in 2016 after challenging the Party's ideology and the role the state-controlled media played in Communist China. At the time his social media account, which had 37 million followers, was deactivated.

Face-saving propaganda drive

China's propaganda apparatus has stepped up efforts in the past month to praise Mr Xi's handling of the outbreak and paint the Chinese government as a saviour for giving the rest of the world time to battle the global pandemic.

The origin of the virus is a sensitive political issue, inflaming tensions between Washington and Beijing. There is a widespread view among Chinese citizens that it was introduced to Wuhan by the United States.

Several top-ranking officials in Wuhan, the city where the outbreak started, were sacked and a doctor who tried to raise the alarm early on but was silenced was given the title of "martyr" last week.

State media and social media censors are swiftly deleting any suggestion that China mishandled the early response and could be in some way responsible for the global pandemic.

Two amateur video bloggers, known as citizen journalists, who were reporting from Wuhan have also reportedly disappeared.

Analysts said Mr Ren's investigation was the latest sign that the President would not tolerate criticism, even from the highest levels in China.

"Xi's critics are all still there ... but at the moment there is nowhere for them to go. It is simply too dangerous to oppose him in any fashion," Lowy Institute senior China analyst Richard McGregor told a live-streamed discussion on US-China relations on Wednesday.

China on Tuesday reported no new deaths from COVID-19 for the first time since January. Travel restrictions out of Wuhan were lifted at midnight on Wednesday. The city was locked down on January 23 after soaring infection rates and deaths overwhelmed hospitals.

China has imposed strict border controls as it battles a rise in the number of imported cases and those without symptoms.