KABUL, Afghanistan: An Afghan official says a group of children set off an unexploded mortar round in a residential area in the eastern Nangarhar province, causing a blast that killed a woman and two children. Attahullah Khogyani, spokesman for the provincial governor, says another seven children were wounded in Sunday’s explosion. He says the mortar round had been fired by insurgents the night before but failed to explode. Afghanistan is littered with land mines and unexploded munitions left over from decades of war, which kill and wound hundreds of people every year.