Five members of the same family have been rushed to hospital after a barbecue exploded during a picnic in the Belanglo State Forest on Sunday.
Paramedics and firefighters arrived at a picnic ground in the forest southwest of Sydney about 12.30pm to find the family distressed and adults and children suffering severe burns.
Inspector John Klepczarek from Bowral Police Station said the family were attempting to light a fire when the blast occurred.
BELANGLO: Emergency services responding to Daly's Clearing Camping area for reports of multi-people suffering burns from BBQ gas explosion,
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"They put some sort of accelerant on the barbecue and it all went up at once like a big ball of fire.
"We are not sure yet why they did it, but it appears the family were crowded around the barbecue area when the explosion occurred."
One adult and one child suffered serious burns to their faces and chests and have been airlifted to Concord Hospital.
The remaining two adults and a child were treated at the scene and taken by road ambulance to Liverpool Hospital.
At least 150 people were in the picnic area when the blast occurred.
Police are still trying to establish the exact cause of the explosion but Inspector Klepczarek said pouring any type of accelerant over a fire is not "the smartest thing to do".