The wrecked building looked as if a bomb had smashed into it from above, collapsing its front into a pile of rubble and damaging homes across the street. “They were normal people, a normal family. Why did Nato kill them?” asked one man who said he was a neighbour. Another seemed to have doubts about what had really caused the explosion. “Was it Nato? That’s the million dollar question,” he said, refusing to give his name and changing the subject when government minders drew near. On Saturday, Nato admitted that one of its aircraft had accidentally hit a rebel column of military vehicles near the oil town of Brega on the front line between the rebel-held east and the mainly government-held west on Thursday.