Firefighters were expected to resume battling the flare-up of a forest fire Tuesday in the Waianae Mountain Range overlooking Makakilo, where the blaze started 10 days ago.

At least a couple of helicopters along with more than three dozen state and city firefighters were called into the battle on Monday.

The fire has charred an estimated 1,025 acres and is at about the 2,000-foot elevation along Palehua Ridge, a fire official said.

Helicopters have been dipping their buckets into a portable pool fed by water from a fire hydrant.

Honolulu Fire Department spokesman Capt. David Jenkins said it’s hard to predict when the fire will be contained.

He described it as the kind of difficult fire that happens once every few years — a fire that gets into the upper reaches of a valley with steep gulches.

"Even getting water drops into the area is difficult," Jenkins said.

No homes appeared to be under threat, but the flames were advancing toward the Honouliuli Forest Reserve, fire officials said.

The initial blaze was started on Aug. 22 by two 7-year-old boys playing with a lighter they had found.

The boys’ father issued a public statement the day after acknowledging his sons’ involvement, urging parents to speak with children about fire safety, and expressing concern for those whose homes were initially threatened by the blaze.

The fire prompted the evacuation of about 20 houses on and around Umena Street as well as another 20 cabins and other structures at Camp Timberline.