China's securities regulator Friday pledged to continue to strengthen measures to prevent insider trading and market manipulation in order to protect investor interests.

Shang Fulin, chief of the China Securities Regulatory Commission (CSRC), said at a business forum in Beijing that a huge number of people with privileged information that could be abused for illegal gains worked in the capital markets.

Shang said the CSRC had investigated 50 insider trading cases in the first 11 months of this year, and 19 people and three organizations have received administrative punishment. Another 15 cases were referred to public security departments.

In the most prominent case, Huang Guangyu, former chairman of Chinese electronics retail giant Gome, was sentenced to 14 years in prison in May after being convicted of illegal business dealings, insider trading and corporate bribery.

The CSRC would strengthen monitoring and control in efforts to prevent insider trading, Shang said at the two-day Caijing Annual Conference 2011, which ended Friday.

According to the Ministry of Public Security, police have dealt with more than 150 major crimes concerning securities and futures since 2002, retrieving economic losses worth more than 30 billion yuan (4.5 billion U.S. dollars). The total sum involved in these cases exceeded 200 billion yuan.