BEIJING -- The "circuit breaker" mechanism, designed to contain wild swings in the markets, calmed down investors and played a positive role in protecting their rights in Monday's trading, China's securities regulator said Tuesday.

The adoption of such a mechanism is new to China and the market needs time to gradually adapt to it, the China Securities Regulatory Commission said.

China will constantly improve the mechanism according to its implementation outcomes.

The Shanghai Composite Index plunged 7 percent on Monday, prompting stock markets in Shanghai and Shenzhen to halt trading for the remainder of the day.

It was the first time China used the "circuit breaker" mechanism it announced late last year.