TANNERSVILLE, Pa. - In the end, Eric Frein finally came out of the woods.

Wearing a black hat and fleece, he walked out in the open under fading daylight, across a scenic yet overgrown former airstrip long ago used to transport honeymooners to the Poconos, and toward an abandoned hangar the self-described survivalist had been using as a shelter.

Spotted and surrounded by a team of U.S. marshals - one of dozens of search squads that for weeks meticulously canvassed a banana-shaped swath of woods stretching hundreds of acres - Frein dropped to his knees, raised his arms, and gave up.

It was a bizarre, nonviolent, and unpredictable ending to a drama that for 48 days paralyzed the region, drained law enforcement resources, and drew international attention.

"I've been involved in a lot of shooting investigations, but nothing quite like this," said Sam Rabadi, special agent in charge of the Philadelphia division of the Bureau of Alcohol, Tobacco, Firearms and Explosives, one of more than a half-dozen agencies involved in the manhunt.

On Saturday, Frein remained in a Pike County jail as investigators sought to understand why he allegedly ambushed a state police barracks in September with a high-powered rifle, killing a corporal and injuring a trooper he didn't know.

They also are working to piece together how Frein, 31, spent seven weeks eluding them. Traveling on foot and carrying a .308-caliber sniper rifle, he led police on an elaborate cat-and-mouse game in the deep woods.

"Clearly, part of [the investigation] is to try to find out exactly what he did every single day," said Edward Hanko, special agent in charge of the Philadelphia division of the FBI.

At least eight times, investigators said, they found shelters where they believed Frein had been hiding. One was a cabin he appeared to have broken into just two days after a search team had cleared it.

And they had concluded from interviews and other evidence that Frein, a military reenactor who liked to consider himself as a survivalist, probably preferred the indoors. One witness told them Frein once chose to sleep in his car rather than on a rain-soaked battlefield. That's one reason they scoured an abandoned hotel complex almost 20 miles from the shooting scene last month.

But they also knew their prey was armed with a sniper rifle, and possibly explosives, and that he was violent and had every reason to be reckless.

His other advantage was their main disadvantage, the one that stretched out before them each morning - what Rabadi called "the vastness of these woods."

"The reason this took so long is that it was such a big wooded area that he was totally familiar with and had a lot of places to hide in," State Police Commissioner Frank Noonan said after Frein's capture. "And we had to be very careful with how we searched it."

In the rugged Pocono Mountains, police dogs lost scents. Helicopters with infrared sensors failed to pick up movements beneath the thick canopy. Even troopers on foot saw barely more than a few yards ahead of them as they trekked through the heart of the forest.

"I've had not just family and friends asking me, but also other colleagues asking, 'Why haven't you caught this guy yet? We don't understand. You have all these folks there,' " Rabadi said.

In interviews and statements in recent days, officials provided a window onto their manhunt. Every morning, they say, officers and agents identified dozens of sections of the area to scour and clear. They drew circles around places where Frein may have been, using tips such as a possible sightings or a campsite he left behind.

Each search team typically included officers with various specialities: a sniper, a negotiator, an explosives specialist, a medic, and a dog handler. They fanned out, with each group canvassing a spot on the grid.

At first, their perimeter stretched over hundreds of thousands of acres. But a huge break came a week into the manhunt when Frein tried to call his parents on his cellphone. The ping from a cellphone tower allowed searchers to narrow the grid to a banana-shaped five-square-mile section of woods on the border of Pike and Monroe Counties.

But even in the densest foliage, a search of even the smallest area could take a day. Clearing the cabins that dot the area took even more time.

The search area included the forest around the Canadensis house where Frein had lived with his parents. (Though the Frein family have not spoken publicly before or since his arrest, they have cooperated with investigators.)

Every few days or so, searchers would find more clues in the woods - like soiled diapers and packages of Serbian cigarettes. Police believe Frein survived on tuna, ramen noodles, and other food stolen from homes and cabins.

At the campsite in Canadensis where investigators uncovered pages of Frein's journal, they also found two homemade pipe bombs. DNA collected from a water bottle at that campsite matched material from a dental pick found in Frein's bathroom at home, according to court documents.

Other tips and information poured in. Investigators said they followed every lead. Some did not pan out. Sightings reported every few days led the search teams to surge and shift.

In the end, the plan worked.

The U.S. marshals team on Thursday was assigned to the area around the abandoned airplane hangar at the Birchwood-Pocono Airpark. The runway and hangar are behind the abandoned Birchwood Resort, which has many empty and deteriorating cabins. It was once a destination for honeymooners, who flew in to stay in the cabins, which are surrounded by white picket fences and clustered around small ponds.

Instead, it became the final hiding place for an accused cop-killer.

Frein is believed to have spent several days in the abandoned hangar - a graffiti-scarred warehouse filled with piles of furniture, paint cans, and scattered odds and ends - leaving when he sensed search teams were approaching and returning to sleep or gather his supplies.

Searching the area after Frein's arrest, officials found firearms, ammunition, journal entries, and other items they believe belonged to Frein.

The journal entries describe Frein's activities in recent weeks, officials said, and add to the handwritten pages found weeks ago at one of his abandoned campsites. Officials said then his writings detailed the Sept. 12 ambush on Cpl. Byron Dickson and Trooper Alex Douglass.

Over the weekend, just 24 hours after Frein's capture, police had cleared the scene and left it to sit vacant, once again open to squatters.

Investigators say Frein has spoken to them since his capture, but police have been reluctant to say what, if any, information Frein has provided to fill in the vast gaps of information.

Officials are also assessing their own efforts, determining which reported sightings of Frein were actually him and how close police were to him as the search wore on.

Most important, officials are trying to figure out his motive.

They believe Frein had a grudge against law enforcement. He spent years planning his attack and retreat, police said, and he posted on Internet forums about wanting to kill law enforcement officials and commit mass murder.

But they don't have all the answers. Yet.

Said Rabadi: "That's the tough part."

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