Sting, the Red Hot Chili Peppers and Peter Gabriel have added their voices to the growing din of support for jailed Russian punk rockers Pussy Riot, who face seven years in prison if convicted of inciting religious hatred.

According to Rolling Stone, the group are on trial in Moscow after a performance in February at which they played a song protesting Russian President Vladimir Putin on the altar of Moscow's main Orthodox cathedral. The song included the line, "Holy Mother, send Putin packing!"

Anthony Kiedis and Flea from the Chili Peppers presented letters of support to Pyotr Verzilov, the husband of accused Pussy Riot musician Nadezhda Tolokonnikova,  and Kiedis wore a Pussy Riot T-shirt on stage during a performance on Sunday in Moscow.

"It's appalling that the musicians from Pussy Riot could face prison sentences of up to seven years in jail. Dissent is a legitimate and essential right in any democracy and modern politicians must accept this fact with tolerance," Sting posted on his official web site. "A sense of proportion -- and a sense of humor -- is a sign of strength, not a sign of weakness. Surely the Russian authorities will completely drop these spurious charges and allow the women, these artists, to get back to their lives and to their children."

Peter Gabriel also wrote the musicians a letter of support, saying, "You have the right to make your own prayers from the heart. I hope you will be released very, very soon. We are all watching."

During opening arguments of their trial Monday (July 30), Tolokonnikova and her band mates, Maria Alyokhina and Yekaterina Samutsevich, denied any criminal intent behind their actions. "If someone was offended by our performance in the Cathedral of Christ the Savior, I am ready to recognize that we committed an ethical mistake," Tolokonnikova said in a statement her lawyer read aloud in open court (according to the New York Times). "This is exactly the error, since we did not have the conscious intention to offend anyone."

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