A woman is being treated in hospital for serious burns to her arms and legs after flames erupted from a barbecue gas bottle on Friday night.

A group of people were having a barbecue at Keast Park after a cricket match about 7.50pm when one of two butane gas bottles exploded or "flamed-out", local police said.

A 40-year-old woman who was standing at the barbecue suffered serious burns to her upper legs and arms.

The group rushed her to the changerooms at the Railway Bowling Club next door and under a shower before emergency services arrived.

Police and three ambulances attended the scene, as did Parkes Fire and Rescue NSW firefighters who secured the barbecue.

The woman was airlifted by a Toll Rescue helicopter to Concord Hospital in Sydney in a serious condition.

Police said only one person was treated for burns after the accident and confirmed no one else was injured.

Officers seized the gas bottle, pending further investigations into the cause of the explosion.