China's top e-commerce group Alibaba Group is preparing to launch a mobile operating system in the third quarter, the Wall Street Journal reported on Tuesday.

The mobile operating system, to be developed by Alibaba's cloud computing unit, will also provide mobile applications, the paper said quoting an unnamed source close to the matter.

An Alibaba Group spokesman declined to comment.

Chinese Internet firms have expanded their mobile presence by developing operating systems, games and applications to tap the high growth of the segment.

China's top search engine Baidu is also developing its own mobile operating system based on Google's Android platform, local media reported recently.

(Reporting by Melanie Lee; Editing by Jonathan Hopfner)