On the first day of the war in Iran, a primary school in the remote town of Minab was bombed. 156 people died, including 120 pupils and 26 of their teachers. Ever since people have demanded answers. Who was behind it? Was it a terrible mistake? If so, how could such a horrific accident have been allowed to happen? Many have pointed the finger at the United States. But in June President Trump told Sky News "I don't think it was who might be responsible. Sky News has spent the four and a half months since the attack investigating what happened, how it happened and Sky's Dominic Waghorn reports from the town - the first journalist from a major western news organisation to go there - where he speaks to survivors, bereaved parents and emergency workers.