New clue in search for Eric Frein

PRICE TOWNSHIP, Pa. (WPVI) -- There is a new clue in the search for wanted gunman Eric Frein. He's been running from authorities for weeks after allegedly ambushing two Pennsylvania State Troopers, killing one of them.

ABC News has learned that investigators are in possession of a letter believed to have been handwritten by Frein.

It was reportedly found in or near the five square-mile search area in Barrrett and Price Townships.

A law enforcement official who is familiar with the case told ABC News that the letter does not offer a motive for the murder of Cpl. Bryon Dickson and the wounding of Trooper Alex Douglas, but it does contain certain details about this case that led investigators to believe that Frein is, in fact, the person who wrote it.

Meantime, state police, the FBI, and K-9 units continue to scour the area one day after the most recent possible sighting of this most wanted fugitive.

We spoke with neighbors in the area who say they never thought the search for Eric Frein would last this long.

Jayne Blair of Mountain Home, Pa. says, "We had an opportunity to go to the beach, and we went. We stayed away a week, but we came back and everything is exactly the same as we left it. So, it's a little disappointing. I was hoping to come back and have it finished."

Larry Wismer of Canadensis tells us, "The helicopters on us. The cosp sometimes, we can't get in to our houses because they think something is happening."

And Tara Ryan, also of Canadensis says, "It's been kind of crazy with the news crews and the police flying down the street and blocking off roads. People not allowed to get back into their homes. It's been hectic considering this is a small town that no one's ever heard of."

There's no word yet if police believe that the letter was intentionally left behind for investigators to find.

State police are continuing to urge anyone with any information about this case to call them immediately.