China's securities regulator said on Friday that it has completed an inspection of private equity and privately offered fund management companies and is cracking down on illegal activities and protecting the interests of investors.

Zhang Xiaojun, a spokesman for the China Securities Regulatory Commission, said the commission conducted an inspection on 305 private equity and privately offered fund management firms in the first half of 2016.

There were a total of 2,462 individual funds involved. They manage 900 billion yuan ($135.7 billion), accounting for 14 percent of the whole private equity and privately offered fund market.

Zhang said the inspection paid attention to financing, asset safety, information disclosure, leverage and any activity damaging investor's interest.

"We found many irregularities. Four institutions are suspected of illegal financing activities and six firms may have damaged investors' interests. Sixty-five did not disclose information as required by regulations and rules," said Zhang.

"All of the institutions with irregularities will be further investigated by public security departments and related local securities regulators," he said.

He emphasized that the CSRC would continue to strengthen regulations on private equity and fund management companies and crack down on illegal activities.

The Asset Management Association of China also released a statement on Aug 1, which said that more than 10,000 private equity and privately offered fund management companies were having their licenses revoked this year.

"The revocation is to protect investors' interests and promote the healthy development of the industry," said the association.

More than 16,000 private equity and fund management companies get their licenses from the association.

The CSRC also said on Friday that it would suspend examination and approval for structured funds. A structured fund combines fixed-income securities and equities to protect investors' capital while at the same time providing the potential for capital appreciation.

"The product design and trading mechanism of structured funds are too complicated for most investors and some problems happened last year, so the CSRC will suspend its examination and approval until it perfects related regulations," said Zhang.