A man has been airlifted to hospital with severe burns after a gas cylinder exploded in his face at a home in Bomaderry.
Emergency services were called to the house at Sampson Crescent after reports of an explosion about 2pm on Monday.
A second explosion occurred just after a fire crew arrived at the scene, a NSW Fire and Rescue spokesman said.
It's believed as many as three gas cylinders were involved in the blast.
A man, aged 30, sustained second-degree burns to his face, airways and both hands in the explosion, according to Ambulance NSW Illawarra district officer Inspector Terry Morrow.
He was taken to Shoalhaven Hospital, before being transferred to the burns unit at Royal North Shore Hospital by rescue helicopter.
A woman believed to be related to the injured man was treated for shock at the scene and taken to Shoalhaven Hospital.
The roof has caved in on the fire-damaged house and power lines have fallen down.
Police and fire crews are investigating the circumstances surrounding the explosion.