TROUTDALE -- Strong winds pushed the Eagle Creek wildfire 12 miles westward through the spectacular Columbia River Gorge and toward Portland suburbs Tuesday, prompting evacuations, coating the region in an ashy film and producing dramatic images of the premier outdoor attraction ravaged by flames.

"I think I can speak for all Oregonians when I say our hearts are breaking," said Multnomah County Chairwoman Deborah Kafoury. "The gorge is Oregon's crown jewel. It's our playground and we are very, very sad."

The fire started Saturday along the Eagle Creek Trail in the gorge and is now burning across more than 10,000 acres, an event described by officials as unprecedented in the reach of ash floating down onto cars, sidewalks and homes in pockets across the metro area.

Mandatory evacuations affected hundreds of homes clustered in small communities throughout in the gorge. Others were on alert to be prepared to leave at a moment's notice.

Interstate 84 remained closed between Hood River and Troutdale.

"Fire burning right along a major interstate, closing 40 miles of road, threatening homes -- this is a big deal," said Dave Thompson, a spokesman for the Oregon Department of Transportation. "This happened fairly suddenly. It blew up."

The U.S. Coast Guard also closed the Columbia River to all marine traffic for 20 miles. The agency decided the falling hot ash and frequent firefighting aircraft landings made conditions unsafe on the river between Reed Island just before Corbett and Bonneville Dam to the east.

Gov. Kate Brown visited the fire command post in Troutdale in the afternoon, thanking firefighters, members of the Oregon National Guard and other first responders for their efforts.

She said the Eagle Creek fire has had a "devastating impact" on the gorge, racing through brush and trees that line the national scenic area thanks to high winds and hot weather without rain.

Oregon State Police announced that a 15-year-old Vancouver boy is suspected of starting the wildfire with what one witness called a "smoke bomb" thrown down a cliff along the Eagle Creek Trail. Brown said the source remained under investigation.

Oregonians should view the fire, she said, as a lesson to be aware of how their actions can affect communities and the environment.

"We are under very dry conditions right now," Brown said. "Whether it's a cigarette, a lawnmower, a car off the road, people need to be extremely careful."

No injuries have been reported and no homes or structures have been damaged so far, fire managers said. State officials said firefighters worked for hours to protect the historic lodge at Multnomah Falls, the state's highest waterfall at about 620 feet.

"It's still threatened slightly, but we made a good save there," Portland fire Lt. Damon Simmons said Tuesday morning as flecks of ash floated from the sky.

He described the sight of flames in the woods around the lodge as "surreal."

"You see the fire above and working its way through those areas where the beautiful falls are and it's pretty heartbreaking," he said.

Fire officials also said the fire damaged the Oneonta Tunnel along the Historic Columbia River Highway, but the extent of the damage wasn't clear yet.

The Multnomah County Sheriff's Office issued a blunt warning to anyone wanting to get a look at the devastation: Stay away.

An influx of curious onlookers have ventured into the Corbett area, complicating firefighting efforts, said Sgt. Bryan White.

They're interfering with efforts to notify residents about evacuation alerts, he said.

"By placing yourself there, you are hindering those efforts and you yourself may need rescue," he said.

Strong winds early Tuesday fueled the fire's explosive growth, including across the Columbia River into Washington. The fire sparked multiple "spot fires" and was burning at Crown Point, along the ridges of Larch Mountain and above Multnomah Falls.

"When fire moves like that, you just have to do what you can, get out of the way and get back in as quick as you can," Simmons said.

Officials said they expect the Eagle Creek fire to become a nationwide "high priority."

"As long as that wind is pushing, that fire will keep spotting and those ember fires are going to keep coming down," Simmons said.

The fire was expected to grow again overnight into Wednesday, but calmer winds are in the forecast and crews hope that may slow the spread, he said.



"We're ready for the worst, we're hoping for the best," Simmons said.

Multnomah County's eastern section was under an state of emergency. The declaration allows county leaders to request additional resources to battle the blaze.

The governor said fire officials also are worried about risks to the Bonneville Power Administration grid and the Bull Run Watershed, which supplies Portland and several other municipalities with drinking water.

"Obviously our top priority is to protect Oregonians and public safety, and of course Washingtonians as well," Brown said. "Second, critical infrastructure. In terms of the gorge, it is a special place for many of us, and we are very concerned about the impact of this fire. ... The conditions are very intense."

On Sunday, state police said they had identified a suspect whose "misuse of fireworks" might have sparked the blaze along the Eagle Creek Trail, one of the most popular in the gorge, running through forestland, by waterfalls and over sheer basalt cliffs.

A woman who was hiking in the gorge said she saw a teenage boy with friends lighting a firework and throwing it into the Eagle Creek Canyon. Liz FitzGerald of Portland said she thought she heard them laughing.

"I saw this shorter kid lob this smoke bomb down into the canyon," FitzGerald told The Oregonian/OregonLive. "I was probably 4 feet away from him. I said, 'Do you realize how dangerous this is? There's a raging forest fire up the trail. This place is so dry.'" Oregon Public Broadcasting originally reported the witness account.

Early Tuesday, only emergency vehicles occupied I-84, kicking up ash and dust as they traveled along the closed stretch of highway. The first flames visible from the interstate, heading east, were just before the Bridal Veil exit. They burned just south of the railroad tracks along Interstate 84 east.

Thick smoke has made air support all but impossible, Simmons said.

"You can't see the ridgetops," he said.

About 400 residences were under mandatory evacuation notices in east Multnomah County. About 280 structures, mostly homes, also were ordered evacuated in Hood River County.

Firefighters from agencies across the region are helping to battle the fire, along with those from the U.S. Forest Service and the Oregon Department of Forestry.

The Portland area, meanwhile, saw up to an inch of ash from the fires.

An air quality alert for northwest Oregon was in effect throughout Tuesday, with "unhealthy levels" from the heat and smoke, officials said.

Relief in several forms might be on its way, the National Weather Service said. First, winds that have been blowing ash and smoke into Portland are expected to shift overnight, so air quality will slowly start to improve as early as Wednesday morning.

The high temperature is supposed to be 85 degrees, a dip from several days of 90 degrees and above. And Wednesday evening, there is a chance of showers and thunderstorms.

Travel was also challenging beyond the closure of I-84, the main east-west route across northern Oregon.

The Washington Department of Transportation issued truck restrictions for SR 14 between Washougal and Dallesport and urged all other motorists to avoid traveling on the highway.

The Bridge of the Gods was open only for those evacuating from Oregon; the Historic Columbia River Highway also was closed.

The communities of Warrendale, Dodson, Larch Mountain, Latourelle, Bridal Veil, East Corbett were under mandatory evacuation orders.

Corbett and Springdale were under Level 2 evacuation orders, meaning residents should be ready to go on a moment's notice.

All other Corbett residents are under a Level 1 evacuation order.

The Corbett School District closed Tuesday and again Wednesday.

Earlier Level 1 evacuation notices in Cascade Locks, meanwhile, are now Level 2, Hood River County officials said. Some neighborhoods were on Level 3.

Emergency shelters were established at the gymnasium at Mt. Hood Community College and at the Skamania County Fairgrounds in Stevenson, Wash.

Level 3 evacuation orders were issued for Archer Mountain Road, Franz Road, Smith Cripe Road, Kellet Road and Victoria Lane, Dimrill Dale Drive and McClosky Creek Road -- all in Washington.

The evacuations were quickly expanded Monday night and Tuesday morning as the fire grew. Multnomah County Sheriff's Office spokesman Lt. Chad Gaidos said the sudden orders were a testament to the fast-moving nature of the fire.

People in areas under evacuation orders "should be out now," said Gaidos. "This is for your safety. We wouldn't ask you to evacuate unless it was absolutely necessary."

Gaidos said a "limited number" of residents opted to stay behind.

(Everton Bailey Jr. and Molly Harbarger of The Oregonian/OregonLive contributed to this report.)

-- Noelle Crombie and Jim Ryan

503-276-7184; @noellecrombie