British jihadi Jack Letts may have been staying at an ISIS jail which the Kurds say was shelled by Turkey last night in a 'clear attempt' to liberate locked up fighters. Explosions in the town of Qamishli, near the Iraqi border, rocked the Chirkin prison where militants from some 60 countries are being kept, guards said on Thursday... Mustafa Bali, spokesman for Kurdish forces in northern Syria, said today the Chirkin prison is where 'the most dangerous jihadists' are held... A senior Kurdish official warned today that ISIS militants could break out of prisons in northeast Syria as fighting intensifies...