An international stock photo company has apologised for selling the rights to prisoner intake photos from Phnom Penh’s infamous Khmer Rouge-era S-21 torture centre, with a company representative saying he was unaware of restrictions on the images’ use and that he was “very sorry if this has caused distress”.

The companies’ sale of the images first came to light last Thursday after regional publication Mekong Review called attention to UK-based photo company Alamy and US-based Sprague Photo Stock selling the digital rights to dozens of photographs from inside the walls of S-21, including portraits of individual prisoners.

For many Cambodian families, these portraits are the only clue linking them to the eventual fate of their loved ones. Nearly all those who entered S-21, also known as Tuol Sleng, never saw freedom again. By the end of the regime, most were taken to Choeung Ek to be killed. That the companies would seek to profit from this tragic history – and the fact that the rights to the photos actually belong to the Cambodian government – raised ethical questions surrounding their use among observers.

As of Friday, both companies appeared to be in the process of removing these photos from their websites – likely in response to inquiries from The Post. At the time that story ran, the companies had not responded to multiple requests for comment.

On Monday, Sean Sprague, of the Sprague Photo Stock library, apologised via email for offering the photos for sale.

I am the "guilty party" who took those photos at Tuol Sleng some ten years ago. I had no idea at the time that there were restrictions as to their use, and thus some of them were placed in my photo stock library as well as at Alamy photo stock.

I am very sorry if this has caused distress and that now there is a "conversation taking place and gaining traction" around this issue, in Cambodia.

I want to say first of all that I have the deepest respect for the Cambodian people and what they have been through during the years of the Khmer Rouge. I have been visiting the country many times since 1966 when I made my first visit, and the last thing I would want to do is cause any offence. By including those photos on my website I was more intent on drawing attention to those terrible years.

But I understand now that it is a copyright issue and that I had no right to try to "sell" those images on a photo stock website, without the express permission of Tuol Sleng museum.

The photographs have now been withdrawn, as you noticed, so I hope this is the end of the matter.

Sean Sprague was not the only photographer credited with such prisoner images on Alamy’s website. Alamy has yet to issue a response of its own.