HONOLULU (AP) — An out-of-control wildfire that has forced about 40 people to evacuate their homes on Oahu was caused by twin boys playing with a lighter, fire officials said Saturday.

The parents of the 7-year-old boys told investigators their sons inadvertently ignited the blaze on Friday in Makakilo, Honolulu Fire Capt. David Jenkins said.

Winds gusting to 30 mph pushed the flames uphill and into a rugged, inaccessible mountain area. The fire was threatening about 20 homes a few miles from the spot where it started.

The flames scorched a wall and door of one home.

Jenkins said crews were hoisted uphill to protect the homes as well as power lines and phone towers.

More than 100 firefighters, aided by water-dropping aircraft, were battling the flames.

There was no immediate word on how much land had been burned.

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