A wildland fire that began Tuesday night and has ravaged 460 acres of native forest above Mili­lani Mauka was 40 percent contained by early Friday afternoon, according to the Department of Land and Natural Resources.

State and federal firefighters used three helicopters contracted by the state and federal governments to continue water drops Friday over that section of the 4,774-acre Oahu Forest National Wildlife Refuge.

The fire has already consumed some of the last remaining Hawaiian sandalwood, ili­ahi, on Oahu. Firefighters detected the scent of it burning Thursday. These and other trees make up this pristine native forest, home to the endangered Oahu ele­paio as well as at least 21 other endangered species of plants and animals.

At 1 p.m. Friday the blaze had blackened 460 acres and was 40 percent contained. At midday Thursday a total of 350 acres had burned, and containment was gauged at 30 percent.

A National Weather Service meteorologist said there were likely light showers off and on Friday.

During the preceding few days there was no rain to help douse the fire.

Several federal firefighters from Hawaii island assisted Oahu personnel in managing the fire Friday. The crews have specialized training in wildland fire suppression, DLNR said.

DLNR does not have a cause for the fire. No structures or houses are currently threatened by the fire.

DLNR Division of Forestry and Wildlife Administrator Lisa Hadway said when native forests are burned, they often do not recover, and the area is taken over by invasive plants and animals, which means a loss of habitat for native species.

"They’re not fire-adapted," she said. "The unique Hawaiian species can’t compete with the invasive species."

Hadway added, "We have such a small land base that when things do burn, they’re gone forever. … They’re almost irreplaceable resources."