|US software giant Microsoft says the company has been questioned by officials from China's business watchdog.
The Beijing News is reporting Microsoft China has confirmed the investigation is related to anti-monopoly issues.
Officials from China's State Administration for Industry & Commerce have visited Microsoft offices in Beijing, Shanghai, Guangzhou and Chengdu on Monday.
Reports are suggesting documents and computers have been seized from their offices.
Microsoft says it is "actively cooperating" with the government.
In May, China banned central government offices from installing Windows 8 on their computers.
At the time, the ban is meant to ensure computer security after Microsoft ended support for its Windows XP operating system, which is widely used on the mainland.
Meanwhile, the company is still pushing forward with plans to release its Xbox One gaming console in China in September, forming distribution ties with China Telecom and e-commerce firm JD.com.