Still, there was "enough evidence to prove that they violated the law, and therefore, they must face charges," Siem Reap provincial court prosecutor Samrith Sokhon said.
The 10 charged Sunday include five people from the United Kingdom, two from Canada and one each from Norway, the Netherlands and New Zealand. Since they are in jail, they could not be reached for comment and it was not immediately possible to find the lawyer representing them.
Police said they raided a rented villa in Siem Reap, where the foreigners were taking part in what organizers called a pub crawl and found people "dancing pornographically" Thursday. While almost 90 foreigners were detained, all but 10 were released.
Photos released by police showed clothed young adults rolling around together on a dance floor.
On Sunday, the 10 were formally charged with producing pornographic pictures, which the prosecutor said were then posted on social media.