Backyard Heater Explodes, Five Suffer Serious And Critical Burns

Five people are in hospital, with two critically injured, after a diesel heater exploded as it was being refuelled.

Police and paramedics rushed to a home on Carnoustie Way at Medowie, north of Newcastle in NSW, around 8.30pm on Saturday night after reports of a serious accident.

They found five people -- four men and a woman -- suffering extensive burns.

A 50-year-old man and the 42-year-old woman sustained severe burns, police said, and were airlifted to Sydney's Royal North Shore hospital in a critical condition.

Police rushed to Carnoustie Way, Medowie. Photo: Google Maps

Three other men -- aged 39, 40 and 54 -- suffered serious burns. They were taken to John Hunter hospital.

"Police have been told the diesel heater was being re-fuelled when the explosion occurred," NSW Police said.

"A crime scene was established, and witnesses are assisting police with inquiries."

The Bureau of Meteorology reported it got as cold as 2.2 degrees overnight in Medowie.