SEATTLE >> Homes across north Seattle were rattled by an explosion this morning that destroyed a house and sent two residents to a hospital.

Two hours later, firefighters were still putting out hot spots and two dozen homes were evacuated while Puget Sound Energy crews worked to stop a natural gas leak, Fire Department spokesman Kyle Moore said.

Metro buses were brought in to shelter residents from the rain.

The explosion around 6 a.m. broke windows in the neighborhood where debris rained down.

Arriving firefighters found the house in flames and a man and woman in their 50s with burns, Moore said. They were taken to Harborview Medical Center. The woman has life threatening injuries; the man is in serious condition.

The flames were visible from Interstate 5.

Puget Sound Energy crews responded, spokeswoman Allison Stanford confirmed.

There had been a natural gas leak Sunday about five blocks away, Moore said. However, it remained for investigators to determine whether a natural gas leaked caused the blast, he said.

"It’s easy to speculate it’s related," Moore said. "We’re saying we want to let investigators have time inside the structure to determine what the cause was."

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.