Some of the biggest names in music are using live shows in Russia to show support for jailed feminist punk collective Pussy Riot, as three of the band's members prepare to go on trial.
Big acts playing Moscow in the past month have raised the case of the trio, Nadezhda Tolokonnikova, Yekaterina Samutsevich and Maria Alekhina, who face charges of "hooliganism" on Monday. They were detained in March following an impromptu performance of a song criticising Vladimir Putin inside Moscow's Christ the Saviour cathedral.
US rockers Faith No More started the trend by inviting members of the group that remain free to join them on stage during a performance at Moscow's Stadium Live club. This was followed by Glasgow band Franz Ferdinand, California rockers Red Hot Chili Peppers and Sting, who all issued messages of support.
Pussy Riot supporters now hope Madonna, who is to perform in Russia next month, will speak up for the three women.
Such high-profile international support, they say, is shining a global spotlight on the crackdown on freedoms in Russia. "They have become a symbol," said Pyotr Verzilov, husband of Tolokonnikova.
Video of the performance, showing the balaclava-clad women shouting for the Virgin Mary to "throw Putin out" went viral. The three could be jailed for up to seven years. Amnesty International has declared the women political prisoners.
The case has captured the imagination of activists around the world, with protests staged weekly. On Friday, Amnesty held a concert in front of the Russian embassy in Washington DC. Beastie Boy Ad-Rock, married to Kathleen Hanna, a pioneer of the feminist punk movement "riot grrrl" that swept the US underground in the 1990s, DJed at one of a series of support concerts in New York.
Anthony Kiedis, lead singer of the Red Hot Chili Peppers, appeared on stage in Moscow in a Pussy Riot T-shirt. He and bassist Flea wrote letters of support to the women, which have been given to them in prison. "I think about you all the time," wrote Flea. "I applaud your bravery and I pray for your release. I will try to make as many people aware as I can."
Russian activists applauded the growing global support. "When these musicians speak their minds they can influence their fans in Russia to think about human rights and what's really going on," said Dmitry Kuminov, a 35-year-old computer programmer holding a pro-Pussy Riot sign at a recent rally for political prisoners. "We have a lot of people inside Russia who don't think about these things."
Fans say there are similarities between Pussy Riot and Madonna, who created a storm of controversy in the late 1980s among religious conservatives with her "Like a Prayer" video and tour. She has already prompted scandal in Russia after promising to use her performance in St Petersburg to stand up for gay rights as the city enforces a law against "homosexual propaganda".
Speaking to NTV, a state-run television channel, in an interview aired on Thursday night, Madonna initially said she had not heard of Pussy Riot, but added later that she was "sorry they've been arrested".
Verzilov has compared the case to that of Chinese artist artist Ai Weiwei. "When governments start to arrest not oligarchs, or even people like [opposition leader Alexey] Navalny, but artists, you can see what is going on," he said. "I'm sure Putin has personally called for this trial."
Prison authorities have repeatedly denied him access to his wife.
Last week, Finnish jazz artist Iiro Rantala said he was cancelling his Moscow gigs and "boycotting Russia" because of the Pussy Riot case.
