Investigations have been initiated on 17 listed Chinese companies because of information disclosure problems, according to the China Securities Regulatory Commission on Dec 17.

By the end of April this year, 2,403 listed companies on the Shanghai and Shenzhen stock exchanges had revealed their 2011annual reports, said the CSRC.

Of all problems found, the largest number were financial accounting ones, which took up 27 percent. Many companies listed on the Chinese mainland diversified their businesses, causing new and complex financial problems.

The number of companies with problems was not revealed.

Other common problems included internal control and information disclosure, the CSRC said.