Microsoft Corp's 6-day-old artificial intelligence chatting robot was blocked on popular instant messaging platform WeChat for a second consecutive day on Monday amid a battle over data security concerns.

The suspension of the Siri-like service, named Xiaobing, was another hurdle in the United States-based company's attempt to popularize its Web search engine among more than 500 million Chinese mobile Internet users.

"While we were in talks with WeChat, all the Xiaobing accounts were shut down without prior notice," said an e-mailed statement to China Daily from Microsoft's Asia-Pacific Research and Development Group, which developed Xiaobing.