An Iraqi refugee has accused the U.S. Military of atrocities against gay Iraqis and claims to have the photographic evidence to back it up.

Two gay Iraqi refugees, who declined to use their real names, delivered a presentation at the Human Rights Campaign headquarters July 24 in which they detailed alleged abuses of fellow gay Iraqis while calling on their audience to donate funds to Helem, a Lebanon-based center that works to address the plight of LGBT people in the Middle East.

One of the Iraqis, who goes by the name “Hussam,” showed the audience of about 80 people gruesome images, including shots allegedly of a beheaded man who was gay and another of the victim’s twin brother grieving over the severed head.

While asserting that anti-gay violence in Iraq is often committed by Iraqis, Hussam also said U.S. service members were involved in anti-gay hostility. For example, he said service members displayed signs in front of their barracks with the words “Fuck Off Fags.”

But the reaction from the audience turned from anger to shock when Hussam said U.S. service members had detained Iraqi civilians perceived to be gay and executed them.

He then showed an image of what appeared to be an American soldier standing in front of a small group of four or five kneeling naked men who were chained together. Hussam claimed the men were gay Iraqis and that he possessed images of their execution, which he did not show the audience.

While there have been numerous reports of violence against gays in Iraq, as reported in the USA Today as late as yesterday, this is the first accusation against the U.S. Military.  Defense officials have not yet commented on the allegations.