BEIJING, Aug. 5 -- China has shut down or suspended several internet companies for spreading erotic content, National Office Against Pornographic and Illegal Publications announced on Wednesday.

The companies, including online storage network Xunlei Ltd., have been issued administrative penalties for spreading pornographic videos and pictures.

Some individuals, including a man surnamed Li, have been found using online storage and popular social networks such as WeChat to distribute obscene content for money. Li and several others have been arrested and put in criminal detention, according to the office.

The office imposed monetary fines maximum of 100,000 yuan (16,000 U.S.dollars) on each company.

Partnering with the Cyberspace Administration of China, it launched a campaign in March to crack down on pornographic, violent or terrorist content on websites to protect minors.

The office also revealed that one publishing house in Hunan of central China has been investigated by local police for pirating textbooks.