An entrance to Four Seasons Hotel in Hong Kong February 1, 2017, where Chinese billionaire Xiao Jianhua was last seen on January 27. REUTERS/Bobby Yip Xiao Jianhua, one of China's richest men, was taken from the Four Seasons Hotel in Hong Kong by Chinese police and put into custody in on the mainland, according to media reports.

The New York Times said Jinhua, who is reported to have financial connections to Chinese President Xi Jinping, was taken across the border on Friday.

His family reported him missing on Saturday, the New York Times said, and then asked to withdraw the missing person filing on Sunday.

Jianhua leads the Tomorrow Group, which is a Beijing-based holding company with investments in different industries such as financial firms and real estate developers. His fortune is valued at around $6 billion (£4 billion).

The Financial Times cited a person familiar with the investigation as saying that "five or six plain-clothed Chinese public security agents" accosted him at his apartment in the Four Seasons at 1 a.m. on the night before Chinese New Year.

The FT said Xiao normally keeps an entourage of female bodyguards but was led away without a scuffle. He is a Canadian citizen with an Antiguan diplomatic passport. The foreign ministry in Ottawa told the FT that "consular officials are in contact with the authorities to gather additional information and provide assistance."

It is unclear why he waas taken and held on the mainland but it echoes actions taken at the end of 2015, when billionaires were arrested amid a government-led nationwide crackdown on corruption.

In December 2015, 48-year-old Guo Guangchang, known as "China's Warren Buffett," who is the head of China's Fosun Group, went missing . Guo is worth an estimated $6.9 billion. His investment group, Fosun, owns Club Med and Cirque du Soleil among others. He reappeared in the US after about a week spent out of contact.

Yim Fung, chairman and CEO of the Hong Kong-listed Guotai Junan International Holdings, went missing in November 2015. Guotai shares tumbled 12% when his disappearance was announced.