WILLSBORO, N.Y. -- Reports of two men walking along a road brought hundreds of law enforcement officers to a small town in the Adirondack foothills for a sweep that seemingly turned up no signs of two killers who escaped from a maximum-security prison, but state police said leads continued to be generated and there would be an increased police presence in the area.
The hunt that began over the weekend focused Tuesday on Willsboro, close to Lake Champlain, after residents reported seeing a couple of men walking on a road late Monday during a driving rainstorm.
Authorities have fielded hundreds of tips since the breakout Saturday from the Clinton Correctional Facility in Dannemora, about 20 miles from the Canadian border and 40 miles from Willsboro, but appeared to have focused most on Willsboro.
At the prison, investigators are pouring over visitor logs and phone records, reports CBS News correspondent Don Dahler. They're also questioning 51-year-old Joyce Mitchell, an industrial training supervisor teaching tailoring to inmates. She has not been named a suspect, Dahler adds.
A law enforcement source confirms to CBS News that calls were made from the female worker's cell phone to possible contacts of the escaped inmates. It was not clear who actually made the calls, however.
Martin Horn, a former New York City Department of Corrections Commissioner, told CBS News, "Until they know for certain that they have these two guys cornered, they're continuing to search every place in the state and outside of the state. ... Eventually they're going to have to come up for food, for water, for something."
In and around Willsboro, searchers walked shoulder-to-shoulder, wearing bulletproof vests and carrying sidearms as they went through hilly woods, fields and swamps, checking every home, garage, shed and outbuilding, then yelling, "Clear!" when there were no signs of the inmates.
By early evening, it appeared the sweep had come up empty, and there was no confirmation from police that the escaped convicts had been there. New York State Police issued a statement Tuesday saying that more than 400 corrections and other law enforcement officers were in the area and planned to go door to door, checking homes and seasonal camps.
People in Willsboro, like Jessica Souza and her son Chase, were told to stay inside and lock their doors, Dahler says.
"If they are cornered and they're desperate, they're going to go into someone's house and someone's going to get hurt," she remarked to CBS News.
David Sweat, 34, and Richard Matt, 48, cut through a steel wall, broke through bricks and crawled through a steam pipe before emerging through a manhole outside the prison grounds.
They were discovered missing early Saturday after stuffing their beds with clothes to fool guards on their rounds and leaving behind a taunting note: "Have a nice day."
There was speculation that the inmates had arranged for someone to pick them up outside the prison and were long gone from the area, even to Canada or as far as Mexico.
The escape from the 3,000-inmate state prison has raised suspicions the men had help on the inside.
Investigators have been questioning prison workers and outside contractors to try to find out who may have supplied the power tools. Contractors have been doing extensive renovations at the 170-year-old prison, a hulking, fortress-like structure that looms over Dannemora's main street.
Investigators remain focused on how the men were able to obtain those tools.
Rich Plumador was a maintenance worker at the prison for 35 years.
He told CBS News, "Everything is counted at the end of the day and if there's one tool missing or misplaced the whole shop gets locked and nobody leaves."
Corrections officials said an inventory of the prison's tools has shown nothing missing so far.
Plumador was surprised the escapees were able to us the tools to get out. "With a grinder or however it was with the sparks, the dust, is unbelievable," he said.
A $100,000 reward has been posted for information leading to the men's capture.
Sweat was convicted in the 2002 killing of a sheriff's deputy and was doing life without parole. Matt was serving 25 years to life for kidnapping and dismembering his boss in 1997.