A two-alarm accidental fire at a home in southwest Bainbridge Island late Saturday night started from a propane barbecue grill.

BI Deputy Chief Jared Moravec said Tuesday that the barbecue had ended, but somehow the deck caught fire. That spread to the outside of the house and then the interior.

Firefighters tried a quick knockdown at the outside of the house on Fort Street near Fort Ward Park. They then moved to the inside, but they couldn’t get access when it extended to the attic.

“We had a hard time getting control of the fire,” Moravec said, adding it wasn’t officially out for a few hours.

A second alarm was sounded due to the size of the blaze and the high temperatures. “Rotation of personnel was needed” to keep firefighters safe, he said, adding that’s why the response was “robust.”

All the occupants got out safely. No one was injured. The house sustained major damage and is inhabitable, Moravec said, adding there never was concern about the fire spreading to other houses.

Over 50 firefighters fought the blaze. Along with BI, they came from Poulsbo, North Kitsap, Central Kitsap and Navy Region Northwest.

Four water tenders were used “to provide a little bit more water,” Moravec said, adding reports that there was a shortage of water were inaccurate.