Islamabad, according to a city official. Police officials say a suicide bomber detonated a device after approaching the gates of the Shia mosque in the Tarlai area of the city, while eyewitnesses have told the BBC the blast was preceded by the sound of gunfire. An emergency was declared as hospitals began to receive the wounded, with an appeal sent out for blood donations. Pakistan's Prime Minister Shehbaz Sharif has condemned the incident, expressing "deep grief". In a statement released on social media, he called for a thorough investigation and the immediate identification of those behind the attack. Pakistan's President Asif Ali Zardari said in his own statement that "targeting innocent civilians is a crime against humanity".

Zaheer Abbas was inside the Khadijatul Kubra Mosque praying when he first heard the sound of bullets. "After that, we bowed and then prostrated, and then there was an explosion," he told BBC Urdu. "After which there were injured people lying everywhere." Pictures from the mosque in the aftermath show footwear scattered across the floor, shattered glass, and people sat among the wreckage. Abbas, who said he "lost his senses" in the moments after the explosion, was eventually pulled out by emergency services and taken to hospital, where he was quickly released. "Fortunately, I did not suffer much injury," he said. (BBC)