Firefighters found this onion bomb hidden in bushes in Salford near where the boys were injured.
They've confiscated it and are warning of the dangers of fireworks.
Onion bombs aren't meant to be available to the public.
More top news
Grass pollen counts remain low for the new week. Some weed and fungal spores airborne. Grass season in decline
Wet and changeable start to the new week - very windy at times with blustery showers at the coast
Cloudy with a little rain on Monday and it's all downhill for the working week! Rather mixed for Lytham Festival. Read on for more detail...