At least nine people, some of them children, have been killed in a blast at a house in Pakistan’s north-western Khyber tribal area, reports say. The explosion took place in the Tirah Valley, which has seen clashes between Taliban militants and the military. were among those killed but it is not clear if the house belonged to a tribal elder or a member of a militant group. Officials say they are still investigating the nature of the blast. One report suggests that it was set off when explosives were being prepared, but there is no official confirmation of this. “The initial information suggests that the blast triggered by explosives killed at least 10 people including three children and wounded nine others,” senior administration official Nasir Khan told the Agence France-Presse news agency. He said that the explosion took place in the reception area of the home of a tribal elder. In recent years the region has seen fierce fighting as the army and several militant groups all vied to control the area, forcing thousands to flee.