By Julie Zhu and Kane Wu

(Reuters) -Chinese dealmaker Bao Fan, founder of investment bank China Renaissance Holdings Ltd, has gone missing in the latest disappearance of a top business executive, unnerving investors and sending its stock down as much as 50% on Friday.

The mainland China-based boutique bank said in an exchange filing late on Thursday the company had been unable to contact Bao.

China Renaissance's board was not aware of any information that indicated Bao's "unavailability is or might be related to the business and/or operations" of the group, which, it said, was continuing normally.

The dealmaker's disappearance is the latest in a series of cases of high-profile Chinese executives going missing with little explanation during a sweeping anti-corruption campaign spearheaded by President Xi Jinping, though the reasons for Bao's disappearance are unclear.

In 2015 alone, at least five executives became unreachable without prior notice to their companies, including Fosun Group Chairman Guo Guangchang, who Fosun later said was assisting with investigations regarding a personal matter.

China's ruling Communist Party in 2021 turned its sights on the country's vast financial sector, kicking off a new round of a years-long campaign to uncover corruption and illegal dealings.

The disappearance, coming after China's post-pandemic border reopening, has renewed focus on boosting the sagging economy has brightened the outlook for deals, as has an easing of a regulatory crackdown on technology firms.

The disappearance of Bao, also the company's controlling shareholder, chairman and CEO, drove China Renaissance's Hong Kong-listed stock to a record low of HK$5 in early trade, wiping off HK$2.8 billion ($360 million) in market value.

The stock regained some ground later in the day to end down 28% in a Hong Kong market that fell 1.3%. Nearly 30 million shares of the boutique investment bank changed hands on Friday, the highest on record.

Bao who previously worked at Credit Suisse Group AG and Morgan Stanley, has been hailed as one of China's best-connected bankers.

He was involved with major technology mergers including the tie-up of ride-hailing firms Didi and Kuaidi, food delivery giants Meituan and Dianping, and travel devices platforms Ctrip and Qunar.

"If a listed company voluntarily discloses that a senior manager or a major shareholder cannot be contacted, it's truly unusual, as the person might have been out of reach for some time," said Dickie Wong, executive director of research at Kingston Securities.