Manhunt intensifies for 2 escaped killers near Dannemora

DANNEMORA, N.Y. (WABC) -- The manhunt for two inmates who escaped from an upstate New York prison intensified on Thursday as police using dogs and helicopters blocked off a main road and concentrated their sixth day of searching on a swampy area just a couple of miles from the institution, situated about 20 miles from the Canadian border.

Schools were closed, and residents received automated calls warning them to lock their doors, close their windows and leave outside lights on.

Gov. Andrew Cuomo said that investigators had received tips that the convicts were in the area, and that tracking dogs had picked up the scent Thursday morning.

"We had tips yesterday they were in Vermont. We have tips today that they're in the immediate area so you just follow every tip and we don't have any hard information one way or the other," said Cuomo. "We're following every tip, that's all I can say. Look - They could either be 4 miles from the prison or they could be in Mexico, you just don't know."

The search for the two inmates focused on a wooded area in Cadyville, New York where the Clinton County district attorney told ABC News authorities believe they found the spot where the men bedded down.

Convicted murderers David Sweat, 34, and Richard Matt, 48, were reported missing from Clinton Correctional Facility, located about 20 miles south of the Canadian border, on Saturday.

There has been no confirmed physical sighting of either man.

Thursday's search involved more than 500 law enforcement personnel, along with K9 and aviation units. Officials closed Route 374 between General Leroy Manor Road and Rand Hill Road in Plattsburgh during the search.

The 1,500-student Saranac Central School District called off classes Thursday because of all the police activity in the area just four miles east of the prison. District Superintendent Jonathan Parks says state police requested he close the schools.

The district offices are just a half mile from the prison's walls.

At a news conference outside the maximum-security prison on Wednesday, New York State Police Superintendent Joseph D'Amico said, "I have no information on where they are or what they're doing, to be honest with you."

But authorities expanded the search after investigators learned that the inmates had talked before last weekend's breakout about going to neighboring Vermont.

"We have information that suggests they thought New York was going to be hot. Vermont would be cooler, in terms of law enforcement," Vermont Gov. Peter Shumlin said at the news conference with New York Gov. Andrew Cuomo.

Shumlin and other officials would not say how authorities learned that information.

Vermont authorities are patrolling Lake Champlain and areas alongside it, Shumlin said. Cuomo urged the people of Vermont to be on the alert and report anything suspicious, warning: "Trust me, these men are nothing to be trifled with."

Former FBI executive and ABC News security consultant Steve Gomez ran through some of the advantages and pitfalls of where the men might have gone in a story featured on ABCNews.com.

Corrections officers, other inmates and contract employees who worked at the prisons are among those being interviewed by investigators, and D'Amico confirmed that training supervisor Joyce Mitchell was among the interviewees.

"She befriended the inmates and she may have had some role in assisting them, but I'm not going to go into any further details," D'Amico said.

Two sources briefed on the case told ABC News the NYS Dept. of Corrections investigated Mitchell within the past year over an alleged relationship with David Sweat, one of the two escapees. The investigation ultimately concluded there was not enough information to take any action against her. A spokeswoman for the Dept of Corrections and Community Supervision declined to comment. State Police told reporters Wednesday Mitchell "was befriended or she befriended the inmates and may have had some sort of role in assisting them."

ABC News previously reported, according to sources familiar with the case, authorities had questioned Mitchell over whether she was supposed to drive a getaway car Saturday night. If so, she never showed, instead checking into a hospital 40 minutes away complaining of a panic attack. The sources say the inmates didn't appear to have any other getaway plan which may be why Sen. Chuck Schumer said it seems "a very real possibility" Matt and Sweat are on foot and remain local.

When asked about who they're interviewing, Cuomo said they're talking to "several people who may have facilitated the escape." He added that if someone who worked at the prison assisted in the escape, then "you'll be on the other side of the prison you've been policing and that is not a pleasant place to be. I can tell you this, anyone who we find cooperated with the escape or facilitated the escape, that is a crime in and of itself and we will prosecute that to the fullest extent of the law."

The killers' mugshots have been put on more than 50 digital billboards in New York, New Jersey, Massachusetts and Pennsylvania, police said, and a $100,000 reward has been posted.

Law enforcement officials again asked the public to report anything out of the ordinary