Sewer explosion happened when the child drop a firecracker down the manhole

a boy thrown into the sewer covers when accidentally detonated biogas in the street when playing with firecrackers, the spot was blown fly. In the meantime, the boy was blown up into the air with the manhole cover. When the boy fell to panic and ran away to avoid it, he was fortunate to have not exploded, and the boy did not get in the way.