Mitchell has not been charged with a crime and her son, Tobey Mitchell, strongly denied that she was involved in the prison break.
"She is not the kind of person that's going to risk her life or other people's lives to let these guys escape from prison," he said.
The two men were said to have been seen walking near the centre of Willsboro on Wednesday, during a heavy rainstorm, before fleeing across a field when a motorist approached. "Everyone in this town probably has a gun and now they probably have it loaded," said army veteran Ron Hamel, 54.
"I can't run because I've had knee surgery, but I've got a baseball bat and I can swing."
He said many residents think the inmates are much further away, in Mexico or Canada, unless the arrangements for their getaway had fallen through.
"I went out to check my barn. People are wondering why on earth they would come to Willsboro, there's nothing here," Hamel said.
"People are very much on the alert, but there are some jokes, too - my wife told me to lock the doors, we don't normally, and I said 'How will I get the $100,000 reward if we do that'?"
Hamel used to work at a juvenile detention centre, while his son works at the county jail, and he knows many of the workers at the Clinton prison in Dannemora, where Matt was serving 25 years to life and Sweat was serving life without parole, for separate murders.
Chuck Moynan, 69, a retired youth prison worker who was volunteering at the visitor centre in town yesterday, said the search in the forest surrounding Willsboro was intense.
"The Swat teams are carrying AK-47s and there are state and local police and correctional department staff all out looking for these guys here, going through the woods."
The search is also continuing in the area around Dannemora, in an attempt to retrace the steps of the inmates after they emerged from a manhole in the street in the dead of night.