Scores of Honolulu and federal firefighters spent yesterday battling a churning brushfire that blackened approximately 150 acres in Waiawa and forced the closure of H-2 north-bound lanes for five hours through the afternoon and early evening.

With flames fanned by the wind and smoke darkening the sky, the fire put on a spectacular show that could be seen for miles. Thousands of motorists were stranded when H-2 north-bound was closed, but ultimately there were no injuries and no structures were threatened.

The fire had been partially contained with only a few active areas when firefighters suspended operations after 8 p.m. They planned to resume "fire suppression" activities this morning.

The fire was first reported shortly before 1 p.m. in a gully off H-2 and Ka Uka Boulevard.

About 60 Honolulu Fire Department firefighters, 11 engines, four tankers and two helicopters responded to the fire. They were joined by 10 federal firefighters, who brought one engine, two additional tankers and a brush truck. A Honolulu Police Department helicopter also assisted with water drops.

In addition, two city and county heavy equipment operators used bulldozers to create fire breaks and extend access to the blaze.

HFD spokesman Capt. Terry Seelig said firefighters concentrated their efforts on fronts advancing toward Mililani and Pearl City.

The department ordered the shutdown of the H-2 north-bound lanes to allow for the movement of vehicles and equipment, and to prevent potentially dangerous situations should the fire reach the highway.

Seelig said the fire came within 300 yards of the highway at one point.

Firefighters were especially concerned that the fire might compromise Hawaiian Electric Co. power lines in the area. However, they were able to keep the blaze from reaching the poles. HECO said it was not necessary to reroute power from the lines.

Firefighters also focused on preventing the fire from moving further toward Pearl City, where it could have endangered a storage facility.

Throughout the day, the three helicopters circled over Ka Uka, dumping water on strategic areas of the fire and refilling their buckets from a plastic reservoir set up in a nearby park.

Dozens of residents and passers-by lined up along a fence on the opposite side of the highway for a clear view of the charred hillside and the billowing smoke that darkened the roadway.

Mike Dau, 52, of Kipapa Gulch said the fire should have come as no surprise given the dry haole koa and grass on the exposed ridge.

"That's going to keep on smoldering for days," he said.

Dau was one of thousands left stranded in traffic due to the road closure. He said it took him more than an hour to drive in from his job at the airport, a commute that normally takes him less than 15 minutes.

Josh Hale, 35, of Honolulu was on his way to visit friends in Mililani when he found himself caught in the traffic backlog. He ended up inching his way to Waipahu then backtracking.

He questioned the necessity of closing all of the north-bound lanes.

"I've driven through fog thicker than this," he said. "I can see it if they needed a lane for emergency vehicles, but why close all of them?"

Last week, dry conditions, low humidity and strengthening winds prompted the National Weather Service to issue a red flag warning for leeward areas of the state, indicating the increased potential for runaway wildfires.

Waiawa Ridge has been the site of several brushfires this summer. Seelig said yesterday's blaze was not related to a brushfire in the same area earlier in the week that burned 350 acres.