A natural gas leak inside a home caused an explosion and fire that destroyed a north Seattle home and injured two residents, and has prompted the utility company to look for other leaks in a 5-square mile area, fire and utility spokesmen said Monday.
A couple who lived in the house thought they smelled gas Sunday night but weren't sure so they didn't report it, Seattle Fire Department spokesman Kyle Moore said.
"When they woke up this morning and smelled something, they were turning on things and `boom!' _ the explosion," Moore said.
The gas fumes apparently were sparked by an appliance, he said.
The couple _ in their 50s _both suffered second-degree burns. The woman was in serious condition in the intensive care unit and the man was in satisfactory condition at Seattle's Harborview Medical Center, hospital spokesman Susan Gregg said Monday afternoon.
The woman has life threatening injuries. The man in serious condition and was able to talk to investigators.
The explosion around 6 a.m. Monday rattled homes across north Seattle. It broke windows in nearby homes and debris fell a block away. About two dozen homes were evacuated. Metro buses were brought in to shelter residents from the rain and a neighborhood church was used as a shelter.
Later in the day, investigators determined that a tree that downed a power line on Sunday caused electricity to travel through the trunk and into the ground, puncturing gas lines as power surged, said Puget Sound Energy spokesman Roger Thompson.
That surge damaged other gas lines in the neighborhood, which caused the reports of leaks nearby the explosion on Monday.
Thompson said crews are working to survey gas lines in the neighborhood, although he said people are safe to stay home.
"As always, if people are in a home and smell natural gas, they should immediately leave the residence and call 911," Thompson said. "Get out of the area, do not turn on or off any appliances or any lights."
Jordan Entler, who lives on the third floor of a building across the street, said the explosion knocked pictures off his wall.
"I thought it was an earthquake, or something that had landed on my roof," he said. "Then I went outside and saw this big ball of flame."
He went to the neighbors' home across the street and made sure they were able to get outside. All of the windows on the back side of their house were blown out, Entler said.