(Yicai Global) June 6 -- China's securities regulator is investigating three certified public accounting firms, putting a temporary halt on their handling of mergers and acquisitions for listed clients.

The companies under investigation by the China Securities Regulatory Commission are BDO China Shu Lun Pan Certified Public Accountants, Ruihua China Certified Public Accountants and China Dahua Certified Public Accountants, Tencent News reported, citing an unidentified CSRC insider. Their business on initial pubic offerings and private placements is unaffected.

The three companies ranked among the top 10 CPAs in China last year by revenue, according to figures from the Chinese Institute of Certified Public Accountants. It ranked Shanghai-based BDO China as No. 3.

BDO China may have been involved in the falsification of Guangdong Chaohua Technology's annual earnings report, the insider said. The watchdog investigated Chaohua Technology, a maker of printed circuit boards, last September. In December, the CSRC's Guangdong branch penalized the firm for untrue statements made in its 2014 report.

Editor: Ben Armour