MAKAHA — Arsonists ignited six brushfires on the Leeward Coast yesterday, closing roads and forcing about one quarter of the Fire Department's resources into the area to battle the blazes.

The fires burned more than 100 acres and required about 150 firefighters to shuttle back and forth from scene to scene as surprised and concerned residents gathered in the streets.

No structures were damaged and no injuries were reported, said Honolulu Fire Capt. Kenison Tejada. But the blazes kept firefighters busy from 1 p.m. until at least 9 last night.

The timing of the fires, their location in remote areas and the absence of power lines or other possible sources of ignition led fire officials to believe they were all deliberately set, Tejada said. There were also "witness accounts from the area," he said.

"We suspect they were all deliberately set," he said.

Fire officials anticipated a dangerous brushfire season and yesterday's blazes push the total to nearly 300 so far, well above last year's pace, according to the department. About 80 percent of those fires are believed to have been deliberately set.

And fire officials fear that the large amount of brush on the ground and the dry, hot summer conditions mean more fires to come.

"We're encouraging the public to pull together. Everybody has to help out," Tejada said. "If anybody sees anything suspicious, you can report it anonymously."

Police were at the scene of at least two of yesterday's fires.

Tejada said the fire department has an agreement with the Honolulu Police Department's CrimeStoppers program that will allow the public to call the hotline with anonymous information about arson suspects.

HPD Chief Boisse Correa said at a news conference in May that police would be setting up surveillance of possible brushfire sites along the Leeward Coast. Police arrested a 13-year-old Nanakuli Intermediate School student in May for allegedly igniting a 3,000-acre brushfire that burned the back bowl of Nanakuli Valley.

Half of the fires yesterday burned along ridge lines and on steep grades along the sides of mountains. Firefighters were forced to hike hoses and water up the sides of the mountains while HFD's Air One dropped seawater on the fire lines.

Some residents of the Leeward Coast expressed anger and anxiety about the blazes yesterday.

Many expressed support for Honolulu firefighters and said they felt sorry that people keep setting the fires.

Jacob Loando, a 24-year old construction worker who was born and raised in Wai'anae but now lives in Ma'ili, said yesterday's fires threatened two of his family's homes, one in Ma'ili, the other in Makaha Valley.

"My wife called me at work and said 'our mountain is on fire,'" said Loando as he sat in his van watching the Makaha Valley fire, which was burning 20 feet from his sister-in-law's backyard. "So many fires these last two months. They (firefighters) been working hard."

"It was scary, the fire was just spreading really, really fast," said Amy Loando, Jacob's wife. "The firemen do a good job, they climb the mountain. They're doing the best job they can. I give them so much credit."

Maurice Cotta, 53, retired in Makaha, owns apartments in the Makaha Valley Towers and the Makaha Valley Plantations, which sit next to each other at the end of Kili Drive. Yesterday, one of the brushfires got within 20 yards of both complexes, sending thick plumes of white smoke wafting through the buildings and out to sea.

"Obviously this is not normal," said Cotta, gesturing to the burning brush from a roadway near the Makaha Valley Towers. "The poor firemen, how can they keep up? Used to be a nice relaxing place but now you're not sure what you're gonna run into. It's gotten to the point (with the brushfires) that you can't sleep at night."

Larry Padayhag, a plumbing supply salesman who lives at the corner of Kulauku Street and Kaukama Road, said he has seen a lot of fires burn the mountain near his home since he moved in four years ago. He said he now accepts the fires as a part of living on the West side. He knows the fire department won't let him down.

"They fast over here the firemen," said Padayhag, as he sat in his driveway watching firefighters hike up the mountain across the street from his house. "They do a good job."