DANNEMORA, N.Y. – The search for two escaped killers from New York’s top-security prison continued locally Monday 10 days after they fled, but Gov. Andrew Cuomo admitted they could be long gone from the Adirondack Mountain area.

“We don’t know if they are still in the immediate area of if they are in Mexico by now,” said Cuomo. “We’re following every lead to the best we can.”

Authorities have received scores of tips on possible sightings of fugitives Richard Matt, 48, and David Sweat, 35. Most of them were local but some extended to Mexico, where Matt once eluded a U.S. murder warrant. More than 800 law enforcement officials are participating in the search.

Clinton County District Attorney Andrew Wylie said because prison worker Joyce Mitchell bailed on a plan to drive the convicts from the scene of their June 6 escape, authorities believe they are still on foot and hiding in the heavily wooded terrain east of the prison.

Mitchell, 51, has been charged with helping the killers escape by providing them with some of the tools used to cut holes in their adjoining cells, break through a brick wall and cut into a steam pipe that led beneath the prison walls to an outside manhole.

Wylie said additional charges against Mitchell, and more arrests connected with the escape, were possible as new details emerge. He has said she agreed to drive the getaway car for the convicts and flee with them to an unknown location but had a change of heart the night of the escape.

“The three of them were going to move on together,” said Wylie. “That was the plan. She got cold feet and realized, ‘What am I doing?’ Reality struck.” He said she couldn’t go through with the Bonnie and Clyde-type adventure because she loved her husband. She befriended the escapees as their supervisor in the prison’s tailoring shop.

Cuomo announced the state inspector general will undertake an investigation into how the convicts managed their brazen escape and the prison’s security protocols. He said any worker or guard who helped with the escape will be prosecuted to the full extent of the law.

“It is critically important to examine the circumstances that enabled these inmates to escape in the first place,” said the governor.

A shackled Mitchell, eyes downcast, appeared briefly in court Monday wearing a bullet-proof vest over a black-and-white striped jail uniform. She waived a preliminary hearing in city court in Plattsburgh, N.Y., in order to transfer her case to the Clinton County Court.

A judge assigned Mitchell a new lawyer after her original attorney, Keith Bruno, said he had a conflict in representing her. The new lawyer is Stephen Johnston, who declined to comment on the case.

Wylie said the investigation into the escape has determined that Matt and Sweat worked on their escape plan for weeks before they broke out of the prison, using power tools at night from a construction site in the prison, returning them to their tool boxes so they would not be noticed as missing.

Wylie said the inmates also became familiar with the inner passageways of the prison, including the maze of pipes and electrical wires, during the weeks leading up to the escape.

Mitchell is accused of providing them with hacksaw blades, chisels, a punch and a screwdriver bit. She first became acquainted with Matt and Sweat in 2013 as their sewing instructor, and later was suspected of having a relationship with both of them. But an internal investigation failed to turn up sufficient evidence of any wrongdoing.

Sweat was serving a life sentence without parole for killing a sheriff’s deputy. Matt was doing 25 years to life for kidnapping, torturing and dismembering his former boss. Matt also served time in a Mexican prison for killing a man there while hiding out from the U.S. murder charge.