Guo Guangchang, head of the Chinese firm that is the main financier of Jeff Robinov’s Studio 8, has disappeared, according to media reports in China.

Investigative publication Caixin Thursday reported that Guo, chairman of Fosun and Hong Kong-listed Fosun International, could not be reached by his company staff.

Caixin also cited unconfirmed reports that Guo had been seen in the company of police officers at one of Shanghai’s airports.

Trading in the shares of Fosun International and Shanghai Fosun Pharmaceutical, which are also listed in Hong Kong, was halted Friday. The two companies issued almost identical interim statements saying that the shares will remain suspended “pending the release of an announcement containing inside information.”

Guo’s personal social media account on Weibo — roughly similar to Facebook — has been emptied of all content.

The disappearance has reignited speculation that Guo may be implicated in a corruption investigation. Guo is the 11th wealthiest man in China according to the 2015 China Rich List, and has often been compared to Warren Buffet.

He has repeatedly denied that he has been under investigation since 2013. However, in August this year, a Shanghai court found that Guo had inappropriate connections to Wang Zongnan, a business man now serving an 18 year prison sentence for abuse of funds at Bright Food Group, a state-owned enterprise. Guo was alleged to have sold Wang a property at less than its market value some 12 years ago. There was no reprimand for Guo.

Guo has led Fosun in the building of an entertainment empire that extends beyond Studio 8. Fosun International also has stakes in China’s Bona Film Group, Canada’s Cirque du Soleil and Korean talent management film SM Entertainment. It owns the majority of French holiday firm Club Mediterranee and a smaller holding in British leisure group Thomas Cook. Earlier this year Fosun hatched its own film production company, which has not yet announced any projects.

Chinese companies – including Guotai Junan International, Dongjiang Environmental, Century Ginwa Retail and China Aircraft Leasing — have recently seen a string of executives go missing, believed to have been detained by corruption investigators.

A major anti-corruption drive was initiated in China after Xi Jinping became China’s president in 2012. Investigations appeared to start with those in central and regional governments, but more recently the probes have expanded to China’s tens of thousands of state-owned enterprises.

A spokesman for Studio 8 declined to comment. Two sources close to the company said the structure of Studio 8’s financing from its Chinese backer is secure, regardless of any potential turmoil in Fosun’s executive ranks. “That fund is huge and it comes from all over. It’s not like it’s going to close down ,” said one of the sources, who declined to be named.