International rights campaigners on Thursday criticised Azerbaijan for jailing two rock musicians on hooliganism charges as the country prepares to host the high-profile Eurovision song contest. Police detained and allegedly beat up the musicians from the band Bulistan after they criticised strongman President Ilham Aliyev and his family while playing at a protest rally in the capital Baku on Saturday. Singer Jamal Ali, bass player Natig Kamilov and protest organiser Etibar Salmanli were imprisoned for up to 10 days for \"petty hooliganism\". \"No one should be beaten in police custody, even if they\'ve sung or said something that the authorities or others don\'t like the sound of,\" Jane Buchanan of campaign group Human Rights Watch said in a statement Thursday. Human Rights Watch and Amnesty International have called for the allegations of brutality to be investigated. \"It\'s deeply ironic that only two months before Baku takes the world stage for the Eurovision, Azerbaijani authorities are using force to break up and silence musicians performing at a peaceful protest,\" John Dalhuisen of Amnesty International said in a statement earlier this week. The men\'s lawyer Anar Gasimli told AFP however that \"the prosecutors are not conducting an investigation\" into the alleged beatings \"because of public holidays\" in the country this week. The authorities in ex-Soviet Azerbaijan want to use the Eurovision pop extravaganza in May to boost the international image of a country until now mainly known as an energy exporter on Europe\'s fringe. But local campaigners are hoping that media interest in the glitzy competition will also highlight allegations that freedom of speech and civil rights are violated in the oil-rich state. Azerbaijani singers Ell and Nikki won Eurovision in the German city of Duesseldorf in May 2011, giving Baku the right to host the contest this year.