By Cleve R. Wootson Jr.

The Washington Post

About the fire — On Wednesday, two fires merged to form a blaze of more than 50 square miles. The fire has closed a 30-mile stretch of Interstate 84 and forced the evacuation of hundreds of homes on the far eastern fringes of Portland’s metropolitan area. Scorching heat, bone-dry vegetation and winds of 30 to 40 mph pushed the flames 13 miles in 16 hours at one point — an almost unprecedented rate of fire spread, authorities said. Embers from the blaze also were carried by winds across the Columbia River and started a spot fire on the opposite bank in Washington state.

— The Associated Press

Investigators in Oregon believe they know who’s responsible for a wildfire that’s burned nearly 30 square miles, forced hundreds to flee their homes and by Wednesday showed no signs of being contained.

The chief suspects: a group of teenagers who giggled and recorded video Saturday afternoon while lobbing fireworks into a parched canyon.

Warm summer temperatures and nearly nonexistent rain have dried out vegetation and turned the Beaver State’s forests into tinderboxes. Officials warned that the threat of wildfire was high and urged caution as Oregonians descended on the state’s parks and forests over the holiday weekend.

One of the visitors was Liz FitzGerald, who told the Oregonian that she was hiking in the Columbia River Gorge 70 miles east of Portland when she saw a teenage boy hurl a smoke bomb into Eagle Creek Canyon.

Another boy recorded the incident with his cellphone, and some girls in the group giggled as the incendiary exploded in the trees below, sending up what FitzGerald thought was smoke from the fireworks.

“I was probably 4 feet away from him. I said, ‘Do you realize how dangerous this is?’” FitzGerald recounted. “‘This place is so dry.’”

A short time later, she encountered hikers who’d also seen the teens setting off fireworks. The hikers were walking to the trailhead to notify park officials about the teens’ dangerous behavior.

FitzGerald decided to run back to the start of the trail to do the same thing, the newspaper said. By then, she could see flames and smoke. It was obvious that it was a forest fire. And it was growing.

As she ran, she encountered the teens again. She said they seemed oblivious to the ramifications of their actions.

“My adrenaline is through the roof,” FitzGerald said. “I said, ‘Do you realize you just started a forest fire?’ And the kid who had been filming with his cellphone said, ‘But what are we supposed to do about it now?’ And I said, ‘Call the fricking fire department!’”

Investigators have said the fire’s cause was “misuse of fireworks.” The teen with the firebombs was a 15-year-old male from Vancouver, Washington. They found him in the trail’s parking lot and interviewed him. No one has been arrested and no formal charges have been made.

Authorities have not released the teen’s name. Video surfaced on YouTube of police interviewing the teens near the entrance to Interstate 84 after what FitzGerald described as a brief minivan chase.

As investigators build their case, they urged anyone with information about the fire’s start to contact authorities, particularly “anyone who heard fireworks or other explosions in the area of the Eagle Creek Trail/Punch Bowl Falls on Saturday between 10 a.m. to 5 p.m.”

People spewed venom at the offenders on an Oregon State Police Facebook post that sought information.

“How does it feel to know you personally destroyed so many people’s lives and livelihoods,” one woman wrote. “All the trees and animals you’ve destroyed and history. You deserve a Darwin Award. You probably are the most hated person in the region right now. Good job.”

Meanwhile, authorities are trying to contain the fire and contend with its effects. For people in the Portland area, that meant ash falling from the sky in a manner eerily reminiscent of the eruptions of Mount St. Helens in 1980, according to Willamette Week.