The two killers who cut their way out of a maximum-security US prison apparently used tools routinely stored there by contractors before returning them to their toolboxes after each night's work, a prosecutor said.
District attorney Andrew Wylie also said that Joyce Mitchell, the prison tailoring shop instructor charged with helping the men escape, had agreed to pick them up in her car but backed out at the last minute because she still loved her husband and felt guilty for participating.
"Basically, when it was go-time and it was the actual day of the event, I do think she got cold feet and realised, 'What am I doing?'," Mr Wylie said. "Reality struck. She realized that really the grass wasn't greener on the other side."
Mr Wylie said there was no evidence the escapees, Richard Matt and David Sweat, had a "Plan B" once the getaway driver backed out, and no vehicles have been reported stolen in the area.
That has led searchers to believe the men are still near Clinton Correctional Facility in Dannemora, New York state, where the manhunt is in its ninth day, with hundreds of law enforcement officers slogging through mosquito-infested woods, fields and swamps close to the Canadian border.
At the same time, New York governor Andrew Cuomo cautioned that the convicts could even be in Mexico by now.
Mr Wylie said it apparently took a long time for the killers to complete their plan, working methodically between midnight and 5am over many nights.
"They had access, from what we understand, to other tools left in the facility by contractors under policy and were able to open the toolboxes and use those tools and then put them back so nobody would notice," the prosecutor said.
He also said the men had been scouting the tunnel system under the prison at night for the best way to get out.
The convicts used power tools to cut through the back of their adjacent cells, broke through a brick wall, then cut into a steam pipe and slithered through it, finally emerging outside the prison walls through a manhole, authorities said.
Mitchell, 51, has been charged with supplying hacksaw blades, chisels, a punch and a screwdriver. Her lawyer entered a not guilty plea on her behalf.
Mr Wylie told CNN that the two inmates planned to have Mitchell drive them about seven hours away to an unknown destination.
Local residents are on edge with some saying they were keeping guns handy. There was an outpouring of support for the search effort. A restaurant urged people to tie blue ribbons around trees and mailboxes.
"The locals have been awesome," said Sergeant Barry Cartier of Franklin County Sheriff's Department, part of a crew from a neighbouring county working 12-hour shifts. "They come around with food all the time. We've got too much to eat."
Sweat, 35, was serving a life sentence without parole for killing a sheriff's deputy. Matt, 48, was doing 25 years to life for the 1997 kidnap, torture and hacksaw dismemberment of his former boss.