Two men are in hospital with burns following an explosion involving a lorry at a quarry near Bristol.
Four crews were called to Stancombe Quarry on the A370 at Flax Bourton at approximately 4.40pm on Monday after reports of an explosion.
A Great Western Ambulance Service spokeswoman said one man suffered first-degree burns while the other suffered third-degree burns.
Both were taken to Frenchay Hospital, which has a specialist burns unit.
An Avon Fire and Rescue Service spokewoman said: "On arrival, firefighters found a small fire in a liquid petroleum gas lorry trailer.
"Two workers, aged in their 50s, suffered burns to their upper body and faces. One was taken to hospital by air ambulance and the other transferred to hospital by road ambulance.
"Firefighters quickly dealt with the fire and assisted paramedics with first aid to the casualties.
"Their injuries are thought to be serious, but not life-threatening."
The spokeswoman said an investigation into the cause of the explosion was expected to begin shortly.
Stancombe Quarry is run by Tarmac.