According to one official,

...the fake blood was used on Muslim men before they intended to pray, because some Muslims believe that "if a woman touches him prior to prayer, then he's dirty and can't pray." Muslim men also believe that contact with women other than their wives diminishes religious purity.

The investigation is being led by Vice Adm. Albert T. Church III. Several detainnes have made similar charges:

In a yet-to-be-published book, former Army translator Erik Saar said he saw a female interrogator smear red dye on a Saudi man's face, telling him it was blood. Saar's account was first reported by the Associated Press last month. And Mamdouh Habib, an Australian man released from Guantanamo Bay last month, said he was strapped down while a woman told him she was "menstruating" on his face.

One lawyer, Marc Falkoff, said in an interview that when a Yemeni client told him a few weeks ago about an incident involving menstrual blood, "I almost didn't even write it down." He said: "It seemed crazy, like something out of a horror movie or a John Waters film. Now it doesn't seem ludicrous at all."

....Detainee lawyers likened the tactics to Nazis shaving the beards of orthodox Jews or artists dunking a crucifix in urine to shock Christians. "They're exploiting religious beliefs to break them down, to destroy them," said Michael Ratner of the Center for Constitutional Rights, which represents several dozen detainees. "What they're doing, it reminds me of a pornographic Web site -- it's like the fantasy of all these S&M clubs."

Falkoff said some of his clients have also been threatened with rape by male interrogators.