In Pakistan , at least three persons have been killed and 15 others injured today in a blast in a city in southern Sindh province. Police said that the explosion occurred in the basement of a building in the centre of Dadu city. The Police source added that 15 other injured are in critical condition Police cordoned off the area as the injured are taken to the nearby state-run Civil Hospital, where an emergency was declared. No group claimed responsibility for the blast.<br/>