DANNEMORA, NY — (CNN) As role reversals go, it’s pretty striking.

Joyce Mitchell, a prison employee, sits in jail while the two murderers whose escape she is accused of assisting — Richard Matt and David Sweat — are still free and on the run.

Mitchell’s husband, Lyle, visited her in prison Tuesday morning, according to a source with knowledge of the investigation.

Authorities announced after the escape that the husband, too, was under investigation. In recent days, however, sources have told CNN that Joyce Mitchell had relationships with Matt and Sweat — and the relationship with at least one of the men was sexual — and Matt and Sweat had intended to kill Lyle Mitchell upon their escape.

The fugitives broke out of a maximum-security facility in upstate New York 10 days ago, and hopes of finding them anytime soon appear to be on the wane.

A New York state official briefed on the investigation told CNN on Monday that the search has gone cold since last week, when investigators found what they believe were several human tracks and a bloodhound possibly picked up a scent.

Also, a source with detailed knowledge of the investigation said the convicts planned to kill Mitchell’s husband — a revelation that raises new questions for investigators.

There were promising clues in the manhunt last week, the official said, but since then, authorities have come up with little to point them toward Matt and Sweat.

Clinton County Sheriff David Favro said the men could still be in the woods near the prison in Dannemora, New York — or long gone.

While solid information about the killers’ whereabouts seems to be lacking, more details are coming to light about Mitchell’s relationships with them and the escape plot, which one official says could have taken a deadly turn.

Mitchell, a prison tailor, is accused of sneaking hacksaw blades, chisels, drill bits, a punch and other contraband into the two convicts’ hands. She has pleaded not guilty to the two charges brought against her but has been talking to investigators.

Matt and Sweat had a plan to kill Mitchell’s husband, who worked in the same tailoring block as his wife, a source with detailed knowledge of the investigation said.
It’s unclear why, when they intended to do it and how much Mitchell actually knew about that plan.

Investigators are looking into whether the two inmates threatened Mitchell to force her to help in the escape, the New York state official told CNN. Investigators believe Mitchell began getting cold feet about executing the plan but possibly had agreed to be the getaway driver because of threats to her and her husband, the official said.

Sheriff Favro says his gut instinct tells him Mitchell wasn’t the convicts’ main getaway plan, because she “would have been baggage to them.”

“She was the backup plan, not the front plan,” he told CNN.

Mitchell was having a sexual relationship with Matt, the source with detailed knowledge of the investigation said.

She’d also been investigated in the past for an inappropriate relationship with Sweat that led corrections officials to move him out of the tailor shop and keep them separated, said Clinton County District Attorney Andrew Wylie.

Mitchell told authorities that the two inmates picked a destination for their getaway, but that they did not give her any specifics.

“That was the information that she was told by Matt and Sweat — that it was about seven hours away,” Wylie said.

It’s not clear if Mitchell has shared everything she knows, the prosecutor said.

“It’s apparent that she’s trying to be as truthful as possible, but in any of these investigations, we always find out that potentially somebody continues to hold things back for one reason or another, and that may be the case here,” he said.

At this point, investigators can’t say for sure whether anybody else was involved, Wylie said.

Mitchell is now under direct, one-on-one supervision in her cell around the clock.

“Obviously, an inmate of this type of risk that’s gone through this type of stress, this type of pressure, we’re going to want to keep a close eye on,” Favro said.

So far, she’s holding up OK.

“She actually is quite calm,” Favro said. “I think she’s handling things fairly well.”

Mitchell appeared briefly in court Monday.

Wearing a black-and-white-striped prison jumpsuit and with her hands shackled to her waist, she didn’t say anything during the hearing.

Her attorney waived her preliminary hearing after a more than two-hour delay that was needed after her first court-appointed attorney had to drop out because of a potential conflict of interest.

Mitchell has been in jail since last week and will remain there unless she posts a $220,000 bond or $110,000 in cash. If convicted, she could face as long as eight years behind bars.

Meanwhile, the possible leads for tracking down Matt and Sweat keep piling up — more than 870 of them so far, according to New York State Police.

They involve a mishmash of far-flung places: Vermont, Mexico, even a few miles from the Clinton Correctional Facility, the prison nicknamed “Little Siberia” from which the two killers escaped on June 6.

More than 800 law enforcement officials have been popping open trucks, peering into cars and scouring heavily wooded areas in the manhunt.

Motion detectors and cameras have been placed in the woods, and a plane able to fly at high altitude and detect movements on the ground is also aiding in the search, the New York state official said.

The local Saranac Central School District canceled classes last week as the search intensified. Classes resumed Monday, but with an enhanced police presence on campuses during school hours, New York State Police said. It said there will be no outdoor activities.

For local residents, the uncertainty about the fugitives’ whereabouts is troubling.

“I feel so safe with law enforcement around,” said Kate Jarrard, who grew up in the area. “But being in the middle of the woods is a little bit scary at times.”

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