Hundreds of police in body armour have poured into a small town in New York state in the search for two killers who used power tools to break out of a maximum security prison 30 miles away.
The hunt that began over the weekend focused on Willsboro, close to Lake Champlain, in the Adirondack foothills, after residents reported seeing a couple of men walking on a road during a driving rainstorm.
Hundreds of black-clad searchers wearing bulletproof vests and sidearms methodically worked their way shoulder-to-shoulder in the rain through hilly woods, fields and swamps, checking every home, garage, shed and outbuilding.
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.
Authorities have fielded numerous tips since the breakout from Clinton Correctional Facility in Dannemora, about 20 miles from the Canadian border, but appeared to have jumped hardest on this one.
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.
New York Governor Andrew Cuomo inspects an opening in the pipe, where two inmates are suspected to have cut open as part of their escape from Clinton Correctional Facility in Dannemora, New York in this New York Governor's Press Office handout photo taken June 6, 2015 and released on June 7, 2015. REUTERS/New York Governor's Press
A note with a caption "Have a nice day" left on an opening in the pipe, where two inmates are suspected to have cut open as part of their escape from Clinton Correctional Facility in Dannemora, New York, is seen in this New York Governor's Press Office handout photo taken June 6, 2015 and released on June 7, 2015. REUTERS/New York Governor's Press Office/Handout via Reuters
They were discovered missing early on Saturday after stuffing their beds with clothes to fool guards on their rounds and leaving behind a taunting note: "Have a nice day."
Given the meticulous planning that went into the breakout, there was speculation that the inmates had arranged for someone to pick them up outside the prison and were long gone from the area. On Monday, authorities said the inmates could be anywhere - perhaps Canada or Mexico.
Willsboro dairy farmer George Sayward said he saw officers parked next to his barn and they told him they were there because of a possible sighting of the convicts. He said he heard one trooper tell another to call in 100 more men: "The next thing I know, there were a ton of them, by the busload."
State police said more than 400 corrections and other law enforcement officers were in the area.
The escape from the 3,000-inmate state prison has raised suspicions the men had help on the inside.
Investigators have been questioning prison staff and outside contractors to try to find out who 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.
A 100,000 dollar (£65,000) reward has been posted for information leading to the men's capture.
Sweat was convicted for 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.