At least one picture shows an American soldier apparently raping a female prisoner while another is said to show a male translator raping a male detainee.
Further photographs are said to depict sexual assaults on prisoners with objects including a truncheon, wire and a phosphorescent tube.
Another apparently shows a female prisoner having her clothing forcibly removed to expose her breasts.
Detail of the content emerged from Major General Antonio Taguba, the former army officer who conducted an inquiry into the Abu Ghraib jail in Iraq.
Allegations of rape and abuse were included in his 2004 report but the fact there were photographs was never revealed. He has now confirmed their existence in an interview with the Daily Telegraph.
The graphic nature of some of the images may explain the US President’s attempts to block the release of an estimated 2,000 photographs from prisons in Iraq and Afghanistan despite an earlier promise to allow them to be published.
Maj Gen Taguba, who retired in January 2007, said he supported the President’s decision, adding: “These pictures show torture, abuse, rape and every indecency.