"It could have been electrical lines snapping," said Capt. Terry Seelig of the Honolulu Fire Department. "They heard the noises, smelled the smoke and got out. Neighbors called the fire department for them.

"They didn't have smoke detectors, which would have probably alerted them earlier."

The fire at 61 Ohai St. was reported at 3:23 a.m. Firefighters were on the scene within three minutes and had the fire under control by 3:29 a.m. It was extinguished at 4:06 a.m. Twenty-five firefighters responded, Seelig said, and they were able to quickly contain the blaze to a bedroom.

The fire damaged about 25 percent of the four-bedroom home. Initial damage estimates are $100,000 for the structure and $20,000 for contents.

The American Red Cross was called to help the couple, both in their 70s.