DANNEMORA, N.Y. — The intense manhunt for two escaped murderers in far upstate New York has hit its 10th day as a woman charged with helping the killers flee from prison heads back to court.

Prosecutors said Joyce Mitchell, a prison tailoring shop instructor who had befriended the inmates, had agreed to be the getaway driver but backed out 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 realized, ‘What am I doing?”’ Clinton County District Attorney Andrew Wylie said Sunday. “Reality struck. She realized that, really, the grass wasn’t greener on the other side.”

Mitchell was charged with helping Richard Matt and David Sweat escape from the Clinton Correctional Facility near the Canadian border on June 6. She is due in court today in Plattsburgh.

Wylie said there was no evidence the men had a “Plan B” once Mitchell backed out, and no vehicles have been reported stolen in the area.

Searchers believe the men are still near the maximum-security prison in Dannemora. At the same time, Gov. Andrew Cuomo cautioned that for all anyone knows the convicts could be in Mexico, where one of the inmates had fled after killing his boss.

Mitchell, 51, was charged Friday with supplying hacksaw blades, chisels, a punch and a screwdriver. Her lawyer entered a not guilty plea on her behalf. She has been suspended without pay from her $57,000-a-year job overseeing inmates who sew clothes and learn to repair sewing machines at the prison.

Wylie said Sunday that the killers apparently cut their way out using tools stored by prison contractors, taking care to return them to their toolboxes after each night’s work.

“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,” he said.

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.

Workers on Sunday welded shut a manhole at the base of a wall on the side of the prison where the two men escaped. They also sealed two other manholes on the street near the prison.