Sergeant Paul Russell of Halls Gap police said the children, aged 8 and 10 and from Melbourne, were staying in a caravan with their mother on a private bush block at Pomonal East Road, Pomonal.

"They were about to cook some dinner," he said.

"One of the children lit a candle for some light, which ignited some gas vapours, causing an explosion."

Their mother, 42, drove both children to Stawell Regional Health.

"Both children were subsequently air lifted to the Royal Children's Hospital, suffering second degree burns to their faces and legs," Sgt Russell said.

He said the injuries were not life threatening, but the hospital was concerned there could have been some burns to the children's airways.

"Their mother had very minor injuries, but didn't require any medical treatment," Sgt Russell said.

Sgt Russell said the hospital called the police to investigate. 

He said the Country Fire Authority also attended to secure the scene about 11pm.

"From what I can work out, there was no fire as such," Sgt Russell said.

Police do not believe the incident was suspicious.

Royal Children's Hospital spokeswoman Vanessa Whatmough this morning said both children were in a stable condition.