Chinese bourses have halted more than 40 initial public offerings (IPOs) in Shanghai and Shenzhen amid a regulatory probe into several intermediaries in the deals, according to official exchange disclosures.

The Shenzhen Stock Exchange suspended more than 30 IPOs, including public share sale plans by BYD Co’s chip unit, on Aug. 18, according exchange filings. The Shanghai Stock Exchange has pressed the pause button on eight IPOs targeting the city’s tech-focused STAR Market since Aug. 19.

The companies attribute the IPOs’ halt to an investigation by the China Securities Regulatory Commission (CSRC) into intermediaries including Beijing-based Tian Yuan Law Firm, China Dragon Securities Co and CAREA Assets Appraisal Co.

The news was first reported by Chinese media.

Tighter scrutiny on IPOs comes as Beijing launches a flurry of regulatory crackdowns against sectors ranging from Internet to tutoring.

On Monday, China said it would tighten scrutiny over accounting firms in a fight against financial forgery, vowing “zero tolerance” toward misconduct.