China is targeting popular smartphone-based instant messaging services in a month-long campaign to crack down on the spreading of rumors and what it calls “hostile forces at home and abroad,” the latest move to restrict online freedom of expression.

The official Xinhua News Agency said the campaign started Tuesday and the services targeted included WeChat, a service run by TenCent Holdings Ltd, which incorporates social media functions that resemble microblog features and that has surged in popularity the last two years.

Users can use such services to send messages to a select group of friends, or can follow public accounts, run by companies, social groups or celebrities, for example. Some accounts are also used by intellectuals, journalists and activists to comment on politics, law and society, and to post news reports shunned by mainstream media. Some accounts attract hundreds of thousands of followers.

Xinhua said the campaign will target public accounts.

Noting that such services had become popular online communication channels, Xinhua said: “Some people have used them to distribute illegal and harmful information, seriously undermining public interests and order in cyberspace.”

The communist government encourages Internet use for education and business but operates an extensive monitoring system. Operators of social media are required to enforce censorship rules against material deemed subversive or obscene.

In March, WeChat removed at least 40 accounts with content about political, economic and legal issues, suggesting that authorities were tightening control over discussion of sensitive topics.

Earlier this year, the ruling Communist Party announced the creation of an Internet security group led by President Xi Jinping. Observers say authorities are wary of millions of Chinese with Internet access getting ideas that might threaten the Communist Party system.

(AP)