On the run: Eric Frein, 31, escaped police capture again today. He is on the FBI's Most Wanted List

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Fugitive gunman Eric Frein has again evaded the massive police dragnet that has now been hunting him for 16 days as he ran into woods after being spotted in the Pocono Mountains.

Frein, 31, wanted for murdering one state trooper and critically injuring another, managed to flee, although MailOnline understands they have an article of clothing that he left behind.

Frein, who is on the FBI's 10 Most Wanted List, was seen just outside the perimeter of the five-square-mile search area that up to 1,000 cops are manning at any one time.

The sighting led to a huge shift southwards as heavily armed cops were forced to rethink their tactics in their frustrating task of finding the expert woodsman.

The drama unfolded in the Delaware State Forest around 3 p.m. on Saturday, Pat Snively, whose home abuts the Delaware State Forest told MailOnline. She said her son, Cody, 32, was first to see the action.

'My son went out to the garage and he saw a state trooper there,' said Snively, 61, a hotel housekeeper. 'He waved to him and the trooper waved him down and he shouted 'Put the kids in the house.

'He said: "Somebody is in the back." They saw him running back into the woods — they flushed him out and he ran.'

Snively lives on the Snow Hill Falls development just south of the area where cops have concentrated their search for Frein for more than a week.

On Sunday, Pennsylvania State police spokesman, Trooper Adam Reed told MailOnline: 'I can't comment on any possible sightings or evidence found yesterday.

'The Snow Hill Falls area is one we are focusing on, however.'



Snow Hill Falls was reopened to visitors late on Sunday afternoon after more than 24 hours when only residents were allowed in. But the police presence on the rustic estate remained heavy.



When asked whether it was open, one trooper said: 'We'd prefer it if you didn't go up there, but....

'You must realize there is an inherent danger,' he added.

Survivalist: Frein is believed to have taken two guns with him on his flight through the forests - an AK-47, which he later abandoned, and a .308 rifle

Manhunt: FBI and state police, pictured this Friday, have launched a huge hunt through the mountains for Frein

Frein, 31, is the only suspect in the murder of Pennsylvania state trooper Bryon Dickson, 38, a father-of-two. He ambushed him late on September 12 at the Blooming Grove police barracks, and as he lay dying he then shot a second trooper, Alex Douglass, who had gone to Dickson's aid. Douglass is still critically injured in hospital in a serious but stable condition.

Police, who have called Frein a 'coward' and 'an assassin', say he then took off in his green 2001 Jeep but failed to negotiate a turn and plowed into a swamp. They say he then managed to walk 25 miles through dense forest to an area south of the picturesque Poconos town of Canadensis where he lived with his parents and teenage sister.

Saturday's was the first sighting of Frein in four days. Lt. Col. George Bivens, the man heading up the hunt, said Friday he believes Frein, a military simulation fan, is playing games with cops. 'War games if you will,' he said.

Bivens said that in the past, Frein has gone close enough to the police line to be seen but far enough away that they have been unable to shoot at him. Officers are authorized to shoot to kill if they make a positive identification and Frein refuses to surrender.

Extensive: Police, using dogs, cars and even choppers have been searching for Frein for weeks

'War games': Police chiefs hunting Frein believe he is toying with them in his lengthy journey through the forest

Flying high: A helicopter takes part in the search for Eric Frein in Canadensis, Pennsylvania

Cops say Frein had been planning the attack for more than two years judging by evidence they found on a computer he used. They say he bought equipment to make a bunker — which they have not managed to find — and believe that is where he is hiding out.

Police refused to confirm Saturday's sighting, but there was a dramatic increase in activity in the afternoon with hundreds of cops moving south into the area that Snively describes.

Helicopters were seen hovering over the area and police dogs were sent in as the hunt for Frein gets more desperate.

'There were two or three regular helicopters and one big black one — it looked like something out of Black Hawk Down,' said Snively, referencing the 2001 movie about a U.S. military helicopter downed in Somalia.

'It was down so low I could wave at the pilot.

'Obviously the troopers had never seen anything like it, they were taking pictures of it on their cellphones.'

Cordon: Police have set up numerous cordons and checkpoints to stop Frein escaping - to no avail

The choppers were flying so low wind from their rotors knocked over three trees on the nearby property of Snively's daughter and son-in-law Farley and Tom Carvalho and their two sons Connor, 14, and Cole, 8.

One of them fell on electrical lines, knocking out power to the area for several hours.

On the ground, Snively said troopers rushed to the scene, fanning out into the woods, but once again Frein had made a successful getaway.

'They were so quiet we didn't even know they were there,' she said.

Police have said repeatedly that they believe they have Frein surrounded. But Saturday's sighting appears to show he somehow got outside the perimeter they have set up.

Snively said the effect of the search has been hard on her. She had to miss several days' work last week when she could not get out of her neighborhood because of the police cordon. Her husband Larry is bedridden after falling off a roof and her 14-year-old grandson has been traumatized by the action near his house.

'He is petrified. He won't sit out on the porch with us,' she said.

'Really into guns': Frein's sister Tiffany, 18, opened up about him in an interview

Snively lives about two miles from Frein's home on Seneca Lane. Police believe the fugitive is intimately acquainted with acres of woods surrounding his house.

They say they have found soiled diapers, a rare Serbian brand of cigarettes and an AK-47-type rifle that they say he abandoned probably because it was too unwieldy for him to carry as he makes his way through the dense undergrowth.

They believe he still has a .308 rifle. Frein's father Michael, an ex-U.S. Army major say the two weapons are missing from his house.

Frein is known to have read survivalist material that advises the wearing of diapers to allow someone to stay in place for extended periods. He is also known as a heavy smoker who is obsessed with Serbia, a country he has visited at least once.

He was a member of Istocni Vuk - which translates to Eastern Wolves - a military simulation team which reenacts battles from the Yugoslav civil wars of the 1990s.

In an interview with the Times-Tribune newspaper of Scranton, Pennsylvania, Frein's 18-year-old sister Tiffany said her brother was 'really into guns.'

Police have said that Frein has a strong hatred of law enforcement, but Tiffany said that he several years ago he dated a woman who became a police officer.

She told the paper: 'I want this to be all over. At the same time, I don’t want my brother to sit and rot in jail.'