Pakistan jailbreak: Prison attacked by militants Peshawar: Militants have attacked a prison in north-west Pakistan with mortars and are locked in a gunfight with security forces. The violence comes hours before Pakistani politicians are expected to vote for the country's new president. The attack was under way at Central Prison in Dera Ismail Khan city in Khyber Pakhtunkhwa province, close to the lawless tribal regions bordering Afghanistan where Taliban and al-Qaeda-linked insurgents are active. Militants have attacked the Central Prison. They are heavily armed and firing mortar shells," district police chief Sohail Khalid told AFP. The ambush appears to be an attempt to free several militants who are held in the prison, a security official said, speaking on condition of anonymity. The jail holds up to 5000 prisoners including some 300 militants involved in attacks on security forces and sectarian killings, he added. Residents in Dera Ismail Khan reported hearing loud blasts and gunfire, and said the electricity supply to several parts of the city has been suspended. It was not immediately possible to confirm a jail break or any casualties, said Mr Khalid, adding that extra police and paramilitary forces had been called into the area. "The situation is not clear as intense firing is going on between militants and security forces," he said. A local police official said he saw militants carrying rocket launchers and firing at the jail. "Militants were firing rockets at jail and I also heard gunfire from inside the building," the official said, on condition of anonymity. He said that security forces had cordoned off the area around the prison where intelligence agency offices and the police headquarters are located.