SHANGHAI, June 5 (Reuters) - Chinese censors are investigating 52 websites owned by firms including top search engine Baidu Inc and online video business Youku Tudou Inc over the distribution of violent and pornographic content, the official Xinhua news agency said on Thursday.
The investigation comes as Chinese authorities tighten their control over the Internet. In April, China's national anti-pornography office stripped Sina Corp of some online publication licences as part of the crackdown. .
The latest websites under investigation, which include a web portal owned by Chinese Internet firm NetEase, are suspected of distributing shows such as cartoon series Grimm's Fairy Tales that contain violent and obscene content, Xinhua said, without citing sources.
The news agency said the websites could face criminal and civil penalties if convicted by China's State Administration of Press, Publication, Radio, Film and Television (SAPPRFT), but gave no further details.
In April, SAPPRFT hit Internet video sites with rare takedown notices for popular U.S. TV shows such as The Big Bang Theory and NCIS without a clear reason. Such shows are not known to contain controversial sexual or political content.
Xinhua said that the investigation into the 52 websites was part of China's campaign to clean up the Internet. To date, Chinese press and publication regulators have banned 122 online publications and punished 93 websites, the news agency said.
(Reporting by Shanghai Newsroom; Editing by Sophie Walker)