China has shut down 110 websites as part of a national crackdown on online pornography, the State Internet Information Office said Sunday.

Some 3,300 accounts on China-based social networking services, such as WeChat and Sina Weibo, as well as online forums have been deleted in the recently launched "Cleaning the Web 2014" campaign, according to the office.

Close to 7,000 advertisements and 200,000 texts with pornographic content were also deleted.

Commercial websites started to cut porn-related advertisements and news portals moved stories with possible sexual connotations to inconspicuous positions.

Social networking sites blocked a series of accounts which posted sexual images or words, or contact details of prostitutes.

The campaign is in response to the persistent spread of pornography online despite previous crackdowns.