The disappearance of high-profile banker Bao Fan is fueling speculation of a renewed clampdown on China’s finance industry.

Bao’s company, China Renaissance Holdings, said on Thursday it had lost touch with the banker, one of the country’s most prolific dealmakers over the past two decades. China Renaissance shares plunged as much as 50% in early Hong Kong trading on Friday.

Bao has been out of contact with the company for about two days, a person familiar with the matter said, adding that the banker’s family was told he’s assisting an investigation.