Newly-freed Afghan prisoners walks after a ceremony handing over the Bagram prison to Afghan authorities, at the US airbase in Bagram north of Kabul on September 10, 2012. The US on September 10 formally handed control to Afghanistan of more than 3,000 detainees at a controversial prison dubbed the country's 'Guantanamo Bay', but disagreements remain over the fate of hundreds of inmates. Kabul has hailed the transfer of Bagram prison as a victory for sovereignty as NATO prepares to hand over full national security to Afghans and withdraw its combat troops by the end of 2014.