A woman and her three sons were badly burned in a fire and explosion in their home late Monday.

Linda Petersen, 32, and her son Jimmy, 13, were flown by air ambulance to the Intermountain Burn Center at the University Hospital in Salt Lake City after a fire started from a wood-burning stove.Timothy Petersen 12, and Shawn Petersen, 10, also suffered burns and smoke inhalation in the fire. They were listed in fair condition at Castle View Hospital in Price.

Petersen is in critical but stable condition at the burn center with burns over 40 percent of her body. Jimmy, suffering from burns over 29 percent of his body, is listed in serious condition, a hospital spokesman said.

According to Emery County Fire Chief Garth Childs, the fire apparently originated around the stove pipe of a wood-burning stove in the front room of the home. The fire burned long enough to consume most of the oxygen in the room, causing an explosion when carbon monoxide gas reached a critical level, Childs said.

"The explosion prompted Mrs. Petersen and her eldest son, who was in bed, to come into the front room to check out the noise. Movingthrough the room introduced fresh oxygen into room causing a second explosion," Childs said.

The second explosion set the mother on fire and apparently blew Jimmy out of the house. As she ran from the house to roll in the grass and extinguish her flames, she called to her younger sons to get out of the house. She then ran next door to her parents home for help, Sheriff's Capt. Dave Owens said.

Owens said when the first units arrived on the scene the house was fully engulfed in flames. Three units, Elmo, Cleveland, and Huntington, were called to extinguish the fire.