Companies operating in China will be punished if they violate laws, regardless of whether they are domestic or foreign firms, a senior official at the country's economic planner said on Wednesday.

Li Pumin, secretary general of the National Development and Reform Commission, made the comments shortly after the commission said it had fined 12 auto part makers, including foreign firms, 1.23 billion yuan ($200 million) for manipulating prices.

“China is a country ruled by law, everyone should be equal before the law. So, it's no matter whether they are domestic or foreign-funded firms, they will receive a punishment as long as they violate laws," Li told a conference.

The fine is the latest in a series of antitrust probes that China has conducted in the past year that has targeted Chinese and foreign companies, though critics have argued that the high-profile cases were mostly aimed at overseas businesses.