Updated at 2.46pm: Some Chinese government departments are making the move to Linux software and operating systems for security reasons, preferring it over rival Windows NT, Top Group head of research and development, Sanyi Zhou said on Thursday. The Windows operating system is the undisputed leader in worldwide usage, but Linux, an open-source system that can be modified by programmers, is gaining popularity. Mr Zhou, interviewed after his speech at the Comdex/China 2001 conference, said that government organisations are beginning to use Linux because they find it more secure. Top Group is a privately held conglomerate with holdings in some companies, including three publicly listed technology firms on the Hong Kong and Shenzhen stock exchanges. It also produces a beta program of Linux software, called Top Linux, along with industrial software. This year was the first time Top Group had a booth at the annual Comdex/China gathering. Comdex/China, in its fifth year, has attracted about 167 companies to set up booths, and about 80,000 registered visitors.