BEIJING -- The government has launched an eight-month crackdown on the creation, sale and dissemination of illegal and harmful children's publications.

The nationwide campaign, which lasts from February to September, aims to uncover books, cartoons and games which are deemed harmful to children being sold around primary and middle schools, according to a circular posted on the National Office Against Pornographic and Illegal Publications' website on Tuesday.

Sales of publications that promote heresy, superstition, obscenity, violence, instigate crimes, or are found to contain content which is "horrific or cruel," are prohibited, according to the circular.

The campaign will also clean up online social networks that disseminate harmful online games, novels, music, cartoons, to children and the youth, the circular said.

Such websites and applications will be shut down, banned, and operators will be held accountable, it added.

The clampdown is one of several campaigns the office and other government agencies have embarked on since early this year to weed out illegal and pornographic publications and information both online and offline.

To create a cleaner Internet environment, the campaigns focus on striking web portals, video websites and search engines that make and disseminate pornography, addressing the emerging practice of sharing and hosting pornography via cloud storage services and clearing away harmful items that mainly target minors, according to the office.

They have also cracked down on illegal Internet-based media, academic journals, news websites, copyright infringement and piracy, the office said.

The campaigns will go after organizations and individuals that upload obscene text, pictures and videos, owners and operators of websites and webpages that knowingly allow or condone production, replication, publication, sale and dissemination of pornography and other harmful information, as well as providers of other related services.

By holding these organizations and individuals accountable, especially by prosecuting them for criminal offences, the campaigns will thoroughly wipe out the profit equation of disseminating harmful information via the Internet, deal a heavy blow to online criminal activities and issue a stern warning to those in the Internet information service industry, the office said.

This year has already seen a number of related cases busted and a large amount of harmful information eliminated in the campaigns.

In 2015, campaigns of similar nature confiscated more than 15 million illegal publications and shut down 28,000 websites deemed pornographic or featuring other illegal content, figures from the office showed.