Story highlights

NEW: Richard Matt made a painting for Joyce Mitchell; she later gave it to her husband for their anniversary

Prosecutor: Mitchell, a prison tailor shop instructor, told her husband about the escape after it happened

Investigators have expanded the search area as they look for Matt and David Sweat

CNN  — 

Before he broke out of a New York prison, Richard Matt at one point made a painting for the worker who’s accused of helping him escape.

Using a photograph, Matt painted a picture of prison tailor shop instructor Joyce Mitchell’s children, Clinton County District Attorney Andrew Wylie told CNN.

And in April, Wylie said, Mitchell gave the painting to her husband as a wedding anniversary present. In exchange, Mitchell gave Matt a pair of speed bag gloves, similar to boxing gloves.

Now Matt, who authorities have also said had a sexual relationship with Mitchell, is on the run with fellow convicted murderer David Sweat.

Joyce Mitchell is behind bars, accused of helping them break free and sneaking hacksaw blades, chisels, drill bits, a punch and other contraband into the convicts’ hands before they broke out.

And as investigators widen their search for the fugitives, more details are emerging about relationships between Mitchell and the escapees that were years in the making.

Cell phone records subpoenaed

Mitchell had been investigated in the past for an inappropriate relationship with Sweat that led corrections officials to move him out of the tailor shop in 2013 and keep them separated, Wylie said.

That’s the year when she started having a sexual relationship with Matt, a source close to the investigation told CNN. The sexual relationship took place at the tailor shop in the Clinton Correctional Facility, the only known place the two were together, the source said.

No court date has been set for Mitchell, who has pleaded not guilty to the two charges brought against her and has been talking to authorities. If convicted, Mitchell could face up to eight years behind bars.

The recordings of her conversations with investigators could total up to 20 hours, her attorney said.

Investigators have also subpoenaed her cell phone records and found that she spoke with Matt’s daughter at least once, Wylie said.

Prosecutor: Husband didn’t know

Mitchell’s husband, Lyle, also worked in the prison’s tailoring block.

But the prosecutor said Wednesday that Lyle Mitchell didn’t know about the prisoners’ escape plan before it happened and wasn’t aware of his wife’s relationships with the inmates.

After Matt and Sweat broke out, Wylie said, Joyce Mitchell warned her husband that the men were free and had been plotting to kill him.

“She advised him after the escape of what happened, including the possible murder plot,” Wylie said.

Joyce Mitchell’s attorney says that doesn’t mean she was participating in the plot.

“I don’t believe she was involved in any attempt to kill her husband,” her attorney, Stephen Johnston, told CNN. “Just because she heard something doesn’t mean she was going to act on it. … She did not want to be a part of it and did not.”

On Tuesday, Lyle Mitchell was face to face with his wife for the first time since her arrest last week.

The couple spent an hour together and were separated by glass, speaking over a phone in a private, unmonitored conversation, Clinton County Sheriff David Favro said.

“He’s providing support,” said Peter Dumas, Lyle Mitchell’s attorney. “He’s not planning to testify on her behalf.”

Johnston, Joyce Mitchell’s attorney, said he did not know what the two talked about. He described his client’s state of mind as “distraught, very weepy and very upset.”

Did others help?

Investigators are looking at other prison employees as well and haven’t ruled out that they may have played a role in the escape, the source with knowledge of the investigation said.

Officials are also investigating whether other inmates might have helped create some type of diversion before, during or after Matt and Sweat escaped, the source said.

The “honor block” at the prison, a special section that had housed Matt, Sweat and other inmates who’d gone years without significant disciplinary action, has been shut down after their escape and will now be turned into a regular cell block, a source with detailed knowledge of the Clinton Correctional facility told CNN.

Being in the honor block gave inmates privileges such as going outside every day, having hot plates and refrigerators in their cells, and congregating for hours in a central gallery area each evening with fellow inmates, said Rich Plumadore, who worked at the facility for 35 years.

Hundreds of leads

Authorities looking for Matt and Sweat have searched 16 square miles – more than 10,000 acres, which is the equivalent of almost 8,000 football fields – New York State Police Maj. Charles Guess told reporters Wednesday.

Police have also developed more than 1,400 leads, the major said.

Police issued "progression" photos of Richard Matt, left, and David Sweat, showing how they might look now.

Guess reiterated what state police said Tuesday: that authorities are expanding the search to other areas surrounding Dannemora, New York.

There are now 600 local, state and federal law enforcement officers involved in the search, a drop from the 800 involved Tuesday. Guess said that since authorities are “no longer containing a hard perimeter,” they released about 200 officers, but there has been no reduction in the number of tactical, canine, aviation or ground search units.

“There’s no hard evidence that they’re outside the area. That being said, I can’t rule that out,” said Capt. Robert LaFountain, of the New York State Police Bureau of Criminal Investigation.

Asked if authorities miscalculated by spending so much time searching near the Clinton Correctional Facility, the state police captain added, “Absolutely not. We (had) to start from … point zero.”

The captain remains confident that Matt and Sweat will be found, he said.

“We are going to locate the individuals and they will be apprehended,” he said.

With few clues pointing toward where Matt and Sweat went after they escaped, investigators are changing tack.

The search stretched into day 12 on Wednesday. The area that hundreds of law enforcement officers are combing is expanding, New York State Police said Tuesday evening.

Teams will be redeployed to new areas near the prison in Dannemora, New York, police said, saying the shifting search zone was based on information uncovered in the hunt for the fugitives.

Canine units are still searching for a scent that might lead police to Matt and Sweat, who escaped from the maximum-security facility known as “Little Siberia” in upstate New York on June 6.

“We’re putting our heart and soul into this,” Favro, the Clinton County sheriff, said of the search. “I’m confident that we’ll be able to get these two.”

But after earlier promising leads went cold, officials aren’t even sure they’re looking in the right place.

The fugitives could have made it across Lake Champlain to Vermont, and New York Gov. Andrew Cuomo has said he talked to his counterpart there to thrash out a “cooperative agreement” for the search.

Another possibility is Canada, whose border lies just 20 miles north of the prison.

But Jonathan Gilliam, a former FBI agent who has led manhunts, says the killers wouldn’t try to drive past border checkpoints – and going on foot through the thick woods is even harder.

“It’s kind of a harsh environment, cold at night,” he told CNN. “They’re instantly setting themselves up for a fall.”

Holed up in a cabin?

Searchers are scouring parts of the Adirondacks in upstate New York, a 6 million-acre wilderness at the doorstep of the prison. It’s filled with hundreds of cabins, many of them abandoned in the off-season.

Investigators think Matt and Sweat could be holed up in one of them. Or, they warn, the pair could invade a home and take hostages.

But Gilliam says that would be “a big chance to take.”

“If you do that, even if you leave, now you’ve set a footprint for the police to latch onto,” he said.

According to authorities, Joyce Mitchell says Matt and Sweat told her they planned to drive to an unspecified destination about seven hours away.

She backed out of the getaway plan, and it’s unclear what other options the killers had in mind. But driving for that length of time at an average speed of 60 mph would put big cities like Boston, New York and Philadelphia within reach.

Those environments might be easier ones in which to disappear.

“People are very aware of who’s around them” in small towns, said Gilliam. “They’re very aware of what other people are doing. Once you get into a larger city, people just stop paying attention.”

Killer’s ties to Mexico

Even farther afield is Mexico, a possibility that Cuomo mentioned over the weekend.

The country, about 2,000 miles away, features in Matt’s past.

In 1997, he murdered a man near Buffalo, New York, and then fled to Mexico, where he killed another man before being captured.

He had “Mexico Forever” tattooed on his back, police say.

Authorities are offering a $100,000 reward for information leading to the escaped inmates’ arrests.

It’s not clear how much money has been spent, but judging from the boots on the ground, it can’t be cheap.

And time may be increasingly on the killers’ side.

“You can’t sustain this type of a manhunt for very long,” Gilliam said. “It’s just too much of a vacuum of all other resources.”

Prison escape puts staff-inmate relationships in the spotlight

DA: Convicts may have rehearsed their escape route at night

Infamous manhunts: When police have tracked fugitives into the wild

CNN’s Randi Kaye, Julian Cummings, Jason Hanna, Polo Sandoval, Alexandra Field, Carolyn Sung, Shimon Prokupecz, Chris Welch, Jason Carroll, Carolyn Sung and Danelle Garcia contributed to this report.