BEIJING, March 15 (Xinhua) -- China's securities regulators have toughened stance against financial market violations to protect the interest of investors.

Since 2017, the regulators have penalized 339 listed companies for violations including insider trading and market manipulation, according to data from the Securities Times.

Many of the cases involved failure to disclose information in a timely manner. For example, PKU HealthCare, a Shenzhen-listed firm, was penalized last year by the Shenzhen Stock Exchange for failing to announce a shareholder change in time.

The China Securities Regulatory Commission (CSRC) imposed fines totaling 7.48 billion yuan (1.18 billion U.S. dollars) in 2017, up 74.74 percent year on year.

The tough stance has continued into 2018, with 34 administrative penalty decisions already made by securities regulators since the beginning of the year, the Securities Times reported.

On Wednesday, the CSRC levied a record penalty of 5.67 billion yuan on a domestic company for manipulating stock prices, underscoring the country's resolve to root out illegal practices.

Authorities have vowed continued efforts to prevent various financial risks and foster a healthy investment environment. The country's two major stock exchanges released rules recently to force companies to exit the equity market for serious law violations.

The move is a key step to fostering an orderly market and improving investor protection, said Jiang Mingde, a consultant with Yixinweiye Fund.