A woman who was hiking over the weekend in the Columbia River Gorge said Tuesday that she happened across a teenager who threw "a smoke bomb" into Eagle Creek Canyon, igniting the now 10,000-acre Eagle Creek fire.

Liz FitzGerald, 48, of Portland said she's fairly certain that she heard the teenager's friends -- including a boy who was video-recording with his cellphone and some girls in the group -- giggle as the firework dropped down a cliff and into the trees below.

"I saw this shorter kid lob this smoke bomb down into the canyon," FitzGerald said. "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.'"

But her reference to an existing wildfire that had forced the closure of the trail miles ahead and her warnings about reckless behavior drew no response, she said.

"They kept on walking down the trail," FitzGerald said.

Oregon State Police said a 15-year-old boy from Vancouver is suspected of starting the fire. They have made no arrests and are not releasing the boy's name. They are asking witnesses who were on the trail Saturday between 10 a.m. and 5 p.m. to call them at 503-375-3555.

Police already have interviewed FitzGerald. She originally contacted Oregon Public Broadcasting with her account.

FitzGerald told The Oregonian/OregonLive that she was hiking to Punch Bowl Falls to get some relief from the heat when she encountered the teens about 1 1/2 miles up the trail, which begins near Cascade Locks.

After the boy threw the smoke bomb, she said she looked down into the canyon. She saw some smoke that she figured was from the firework.

She didn't see any brush or trees on fire, so she kept walking for about two minutes. That's when she said she encountered two hikers and told them what she saw. The pair told her that they'd seen a group of kids lighting fireworks at Punch Bowl Falls, a short way up the trail, and they were headed back down to "rat them out," FitzGerald said.

FitzGerald decided then that she should return to the trailhead and report what she saw. She didn't have her cellphone with her, so she'd have to do it in person.

"I started to run," FitzGerald said, adding that she soon passed the spot where the she had seen the teens. "At that point, it was so obvious to me that it was a fire. I could see all of this smoke billowing up."

Moments later, she passed the group of teenagers.

"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!'"

FitzGerald said she doesn't think they understood the gravity of the situation.

"There was complete indifference," she said. "It was weird. I was just like, 'You're not getting this on any level. You're not getting this at all.''"

As she made it down the trail, she warned other hikers -- including those with children -- to turn around. But they looked at her oddly and kept going, she said.

Authorities would later report that 150 stranded hikers -- many of them who had only planned on a quick day trip -- had to spend the night on the trail before rescuers led them out on an alternate route starting at dawn the next day.

Once FitzGerald returned to the trailhead, she found a U.S. Forest Service officer and reported what she saw, she said.

After the officer called for fire trucks and a helicopter carrying fire retardant, she told him that she was worried the teens might try to drive off undetected, FitzGerald said.

Just then, she spotted a minivan drive by. A teenage girl in the front seat looked excited, FitzGerald said. FitzGerald thought she might be part of the group.

FitzGerald said the officer asked if she felt comfortable jumping in his SUV and following the van. She said yes, and she and the officer gave chase, she said.

"The kids tore through the parking lot," FitzGerald said.

The officer was able to stop the van a short while later, just as the driver was trying to get on Interstate 84, she said.

FitzGerald praised the officer's quick response from the instant she reported the fire.

She doesn't know what to think of the teens.

“It was a whole group of kids that was completely complicit,” FitzGerald said. “They were all in on it. He (the 15-year-old boy) threw it. But they all shrugged it off. They had no discernible problem with what he was doing.”

Videos posted online by other hikers show police later interviewing two boys who appear to be teenagers near the Eagle Creek Trailhead. The boys – one wearing a tank top and shorts and the other shirtless – are next to a minivan.

One of the videos was taken as hiker Kevin Marnell and his friends watched police detain the boys.

Marnell and his friends expressed shock on the video about the smoke rolling down from the trail. They also remarked about all of the signs they'd seen posted along the trail, warning hikers against using fireworks in the area.

"We were making fun of that because we were thinking, logically as engineers, that no (expletive) idiot on earth would (expletive) do that," a man can be overheard saying in the Marnell video.

Marnell, who lives in North Portland, told The Oregonian/OregonLive that he was part of a group of five friends who had hiked along the Eagle Creek Trail that day, with a stop at Punch Bowl Falls. The group had spread out toward the end of the hike as they returned to the trailhead.

About a mile from the trailhead, Marnell said he heard a loud bang, which he believes was a firework, then saw smoke rising from the forest shortly after that.

"I just saw the smoke rising out of the bushes," Marnell said. "There was so much smoke. It looked really bad."

"Our friend who passed by five minutes later saw a tree on fire," Marnell said. "The last guy in our group said it was so smoky, he couldn't see anything."

Marnell said the teens appeared to be part of a group of four to six young people.

"We didn't see any crying," Marnell said. "There was a lot of their hands on their heads, just looking frustrated and worried."

Oregon State Police, the Hood River County Sheriff's Office and the Hood River County District Attorney's Office are investigating how the fire started.

-- Aimee Green

agreen@oregonian.com

o_aimee

News researcher Lynne Palombo contributed to this story.