KAMUELA, Hawaii — Hundreds of people along the coast of Hawaii's Big Island were ordered to evacuate inland Sunday as brushfires burned out of control.

Nine separate fires appear to have been intentionally set in dry grasses along west coast roads just before 4 a.m. Sunday, said Duane Hosaka, staff officer for Hawaii County Civil Defense. The evacuation order affected an estimated 500 people.

Blazes covering about 700 acres of land near the northwest tip of the island still hadn't been contained by Sunday afternoon as more than 60 fire departments struggled to stop them from spreading, Hosaka said.

No homes had been damaged and no residents were injured, although there was a threat that the fires could approach residential areas with a slight change in Hawaii's temperamental breezes, he said.

"It's still burning out of control," Hosaka said. "If they were to go back home and the fire were still burning ... and we had to close the roads, they wouldn't have any way of getting out."

Two evacuation shelters were opened at an elementary school and community center, where emergency officials expected many families to take refuge if the fires weren't contained before the end of the day, Hosaka said.

Three of the original nine fires blew up and couldn't be contained after more than 8 hours of firefighting efforts.

Those fires were located near Kamuela and north of Waikoloa Village along Akoni Pule Highway, Kawaihae Road and Old Puako Road. They covered between 620 and 720 acres, Hosaka said.

"The fire of primary importance affecting residents is the Puako Road fire because of the endangerment to homes and people," said Big Island Mayor Harry Kim. "If the fires continue through the evening, we'll have to open up a third shelter."

It was pitch black outside when 21-year-old Max Hagen was awakened by a police officer banging on his window in Kamuela at 4 a.m., he told The Honolulu Advertiser. There was a fire outside just 100 feet away from his neighbor's house.

"I went for the family photos," Hagen said. "My mom went into her office and grabbed the tax files and things like that."

The Hagen family decided to stay and not evacuate. Tradewinds blew the smoke and flames in the opposite direction of their home, he said.

Fire investigators hadn't discovered exactly how the blazes were set. Apparently they were started in a coordinated effort by people in cars who lit drought-ravaged grasses nearby, Hosaka said.

"We get calls from people who live miles away. They live up on the mountain and they can see the fires," he said.

Several parks were closed, including Hapuna Beach, Wailea Bay and Spencer Beach Park. Campers staying there had to be evacuated, although no count was available.

In addition to firefighters and police, four helicopters and eight water tankers helped spray water to help douse the blaze.