At least 18 people have been injured when a bonfire exploded at the Yellow Carnaval in Villepinte, north-east of Paris.
The explosion occurred at the end of the carnival, on April 1.
Video posted on social media showed the bonfire blowing up seconds after being ignited, sending debris flying.
According to Le Parisien, a mother and her child are among those seriously injured and the town’s mayor was also hurt.
An initial investigation had been opened by prosecutors, but the cause of the explosion was not yet known, AFP reported.
A police source told the BFM news network that the blast may have been caused by the petrol used to help start the fire.