BEIJING, April 3 (Xinhua) -- More than 2.1 million online animated videos and games featuring popular children's characters in sexual or violent scenarios have been deleted as part of a campaign targeting companies registered in Beijing, local authorities said Tuesday.

Over 50 cases were placed on file for investigation by police, and some 800,000 yuan (130,000 U.S. dollars) in fines were issued for violations, according to Beijing Integrated Law Enforcement on Cultural Market, an agency under the Beijing municipal government.

The campaign run from January to March.

In late January, Beijing issued a notice, asking video websites to purge illegal content, examine and clean up all videos and online games related to disturbing cartoons, which Chinese media has termed "children's evil classics."

Wang Ningzhi, deputy head of the Beijing Integrated Law Enforcement on Cultural Market, said that the city will continue its crackdown on such violations to clean up online content that may harm the physical and mental health of youth.