The head of a Chinese wealth management firm who allegedly fled with more than $150 million in investors' money surfaced in an online video on Monday saying he will "be right back", as police searched for him.

Yang Weiguo, chairman of conglomerate Wangzhou Group, disappeared with around 1.0 billion yuan ($153 million) last week, leaving thousands of investors unpaid, the official Xinhua news agency reported late Sunday.

A wealth management subsidiary which Yang manages, Wangzhou Fortune, has experienced cash flow problems since mid-April, the report said.

Wangzhou Fortune, which has operations in several cities including Shanghai and nearby Hangzhou, issued a statement last week saying Yang had vanished and the company had reported the case to police.

But in a video posted by the 21st Century Business Herald, Yang told investors not to worry.

"Hello everyone, it's me," said a man in a suit jacket and open-necked dress shirt identified as Yang. "Don't worry, I will be right back."

In a separate statement published by the newspaper he denied any wrongdoing.

Wangzhou Group is a conglomerate with a wide range of business areas including logistics, media, finance and hotels, according to its website. It has more than 100 branches in over 50 cities.

The case is the latest involving alleged financial fraud to emerge in China as the economy slows, sometimes leaving investment firms struggling to pay out promised returns.

Earlier this month, police detained more than 20 managers of the Zhongjin group of finance companies, including its head, at the airport as he apparently tried to flee the country on a chartered plane.

Another wealth management firm, Shanghai-based Jinlu Financial Advisors, has also struggled to pay back investors, causing them to besiege its office in the commercial hub.

In another recent scandal, peer-to-peer lending firm Ezubao bilked 900,000 investors out of $7.6 billion by offering high interest rates which it was unable to pay, in what one executive described in a televised confession as a "typical Ponzi scheme".