Authorities in northwest China's Gansu Province said Friday they had caught several cell phone retailers suspected of selling obscene content to mobile subscribers.

In the most recent case uncovered two weeks ago, market regulators seized more than 1 GB of vulgar video, photos and texts from computers and other devices at the privately-run store in downtown Lanzhou, the provincial capital.

The store owner, who authorities did not name, admitted he had sold such content for mobile subscribers, mostly students and migrant workers, for 5 to 10 yuan per GB and helped transmit the content to their cell phones.

Some stores even offered obscene content for free as part of their special cell phone "promotion packages" to attract buyers.

"Obscene content is particularly harmful to youngsters, which is why the government has taken actions," said Meng Yingqi, an official in charge of cultural market administration in Lanzhou.

Meng said the crackdown in the market was very difficult because dealers could easily defend themselves saying the obscene content was private and not for sale.

The Chinese government unveiled a regulation last year to ban pornographic and vulgar content spread through the Internet or mobile WAP sites. More than 140,000 mobile WAP sites that offered pornography to mobile phone users were shut down or blocked in the five-month crackdown.

As part of China's latest efforts to curb porn, a judicial interpretation issued in February further clarified that production, replication, publication, sale and spread of obscene electronic information (video) targeted at minors aged under 14 via Internet or mobile WAP sites was a crime.

China's Internet users reached 384 million at the end of 2009, of which 233 million, or 60.8 percent, browsed webpages via mobile phones, according to the China Internet Network Information Center.