A Canadian electro-industrial band is asking for thousands of dollars in royalties after learning that the US military used their music to torture prisoners at Guantánamo Bay. Skinny Puppy claim they filed a $666,000 (£368,000) bill with America'd defence department.

"We sent them an invoice for our musical services considering they had gone ahead and used our music without our knowledge and used it as an actual weapon against somebody," keyboardist Cevin Key recently told CTV News. "I am not only against the fact they're using our music to inflict damage on somebody else but they are doing it without anybody's permission."

Skinny Puppy first learned about the alleged use of their music from a former Guantánamo Bay guard, who was "affected or offended" by the detention camp's practices. Although the Vancouver-born band originally planned to use their new album cover as an invoice to the Pentagon, they have now received "coaching" and apparently sent an actual physical document to government officials. They are even considering a lawsuit.

"We're not making a point looking for financial gain," Key underlined. But nor is the group entirely surprised that their songs were used as sonic punishment for Gitmo's detainees: "We thought this would end up happening, in a weird way," he admitted in an interview with the Phoenix New Times. "Because we make unsettling music, we can see it being used in a weird way. But it doesn't sit right with us."

Skinny Puppy aren't the only group whose music has reportedly been used to torture terrorist suspects and "enemy combatants" at the United States' base in Cuba. According to earlier reports, interrogators have employed songs by Metallica, Rage Against The Machine, Queen, Eminem, and even David Gray. "It's an issue that no one wants to deal with," Gray said in 2008. "It's shocking that there isn't more of an outcry."

Weapon, Skinny Puppy's 12th studio album, is out now.

Reading on mobile? Watch the video for Skinny Puppy's illisiT here