Fire crews and an ambulance were called after a 15 year-old boy burned his arm after throwing petrol on a bonfire.
The fire in Finchingfield Road, Hempstead, was quickly extinguished and medics treated the boy for burns.
Sub Officer Steve Morris, of Thaxted Fire Station, said: "Incidents like this show how incredibly dangerous it is to put petrol on a bonfire. The boy had lit the fire as part of his World Cup celebrations and was having trouble getting it going.
"No one should ever throw any kind of accelerant on a fire. This boy suffered burns, but it could have been far worse. It shows how dangerous it is and why it is vital to take safety precautions if you are having a bonfire."