Police in the southern Chinese city of Shenzhen have arrested 10 people in connection with a sex scandal that has generated intense public interest.
Mr Chen has apologised to anyone affected by the images
The arrested are accused of copying and distributing explicit pictures showing Hong Kong film star Edison Chen in encounters with a series of actresses.
The several hundred images have been widely viewed on websites since they were posted at the end of January.
It is believed they were taken from Mr Chen's computer when it was serviced.
The pictures, apparently taken by Mr Chen himself, show the actor in bed with a series of famous actresses.
They were published across the internet including on China's most popular search engine, Baidu.
The BBC's James Reynolds in Beijing says the photos have captivated China and caused deep embarrassment to those involved.
A police official told China's Xinhua news agency that the authorities would "severely crack down on the criminal activities of manufacturing, selling and spreading discs of Hong Kong's celebrity photos and other pornography productions".
The Beijing Association of Online Media, a government-backed watchdog, has praised some sites for removing the images and demanded that Baidu apologise for allowing its users to find them.
"Baidu still hasn't implemented effective blocking and obscuring of the photos," it said, adding that the search engine had "become defensive" and "procrastinated".
Edison Chen has issued a video statement in which he apologised to anyone affected by "this strange, strange ordeal."
Pornography is officially banned in China and the internet is restricted and closely monitored by the government.
Our correspondent says that public curiosity over the pictures has been a real test for internet censors.