Last Updated 1:50 p.m. ET
(CBS/AP) NORTH BEND, Wash. - Authorities in Washington state say they've found a body in an elaborate bunker they had surrounded in the Cascade Mountains, and it appears to be that of a man wanted for killing his wife and teenage daughter last weekend.
The King County Sheriff's Office sent word via Twitter on Saturday that they'd found the body, nearly 23 hours after they first located the structure carved into the side of Rattlesnake Ridge east of Seattle.
The suspect was 41-year-old Peter Keller, a heavily-armed survivalist not seen since the killings at his home last weekend.
Earlier on Saturday an explosives team tried, with little success, to blow the roof off part of the heavily-fortified bunker in which police believed Keller was hiding.
King County Sheriff's spokesperson Cindi West described the forested area where the bunker sits as, "pretty close to town but it's in a place where nobody would normally go." SWAT units were airlifted to the otherwise inaccessible location.
Keller had spent nearly eight years carving the elaborate, camouflaged, multilevel bunker into the side of Rattlesnake Ridge, in the Cascade Mountain foothills
SWAT officers who kept watch on the bunker through Friday night said they saw lights going on and off, and they believe its occupant had everything necessary to remain inside for a long time including a generator, food, gas mask, bullet-resistant vest and many guns.
Photographs found in Keller's home after the killings gave authorities an idea of where it was; in one picture that they enhanced, detectives could make out buildings in nearby North Bend. Combined with reports from alert hikers who remembered seeing his faded red pickup truck at the Rattlesnake Ridge trailhead, the sheriff's office sent experienced trackers to the area, where they found off-trail boot prints confirming their belief that he was somewhere on the ridge.
SWAT teams spent a grueling seven hours on the mountainside Friday morning, virtually crawling over dangerously steep terrain slick with mud from recent rains, before they found the bunker. A number of officers were treated intravenously for dehydration, and one broke his ankle, West said.
After long shifts, the officers appeared exhausted, their faces smeared with camouflage paint, as they rode down the mountain in sport-utility vehicles or armored carriers to be replaced by fresher teams.
Authorities pumped tear gas into the structure after locating it Friday, but it failed to flush the occupant either because it didn't penetrate deep enough into the structure, or because the person had a gas mask.
Officers described the bunker as "amazingly fortified" and said the photos recovered from Keller's house don't do it justice, West said.
"It's a very extreme tactical situation," King County Sheriff Steve Strachan said. "Time is on our side. We're not going to do anything rash."
The bunker was found at about the 1,350-foot level, several hundred yards due east of a trailhead at Rattlesnake Ridge. It had several entryways and ladders.
"This isn't a hole in the ground. It's an elaborate structure," Strachan said.
Court documents described Keller as a loner who has a survivalist mentality and has been stockpiling supplies in the woods.
An arrest warrant issued Wednesday accuses him of two counts of first-degree murder and one count of first-degree arson; the home was set on fire after Keller's wife and daughter were shot.
The fire at Keller's home was stopped before the house burned down, and authorities said they found seven gasoline cans placed in different areas of the home.
The King County medical examiner has determined Kaylene Keller, 18, and her mother, Lynnettee Keller, 41, both died from gunshots to the head. Their bodies were found in their bedrooms.
Kaylene's boyfriend told detectives that Peter Keller had shown him his gun collection and several large-caliber rifles and handguns, court documents said. The boyfriend, who was not identified, said Kaylene had told him her father took long hikes on the weekends and was stockpiling supplies at a fort in the woods.
Peter Keller withdrew $6,200 from a bank last week and told one of his co-workers at a computer refurbishing store in Preston that he might not return, according to court documents.