DANNEMORA, N.Y. (CBSNewYork/AP) — As the search for two escaped murderers reached its 11th day, rain is making things difficult.

Rain is washing away any possible scent and disrupting the use of technology such as thermal imaging to detect warm bodies, authorities said Tuesday.

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Clinton County Sheriff David Favro says rain cools the body and makes tree leaves cling together, forming a dense canopy shielding the view from overhead. Helicopters have been used extensively during the hunt.

 

More than 800 law enforcement officers who are searching for David Sweat and Richard Matt have steadily shifted their focus eastward along Route 374 leading from the village of Dannemora, home of Clinton Correctional Facility.

Officers, some with search dogs, made their way through woods in the neighboring town of Plattsburgh, about 5 miles east of the prison.

David Sweat and Richard Matt

David Sweat (left) and Richard Matt (right) (Credit: New York State Police)

Richard Matt, 48, and David Sweat, 35, escaped June 6 from the Clinton Correctional Facility near the Canadian border.

Joyce Mitchell, 51, has been charged with helping the killers flee by providing them with hacksaw blades, chisels and other tools made a second appearance in court Monday.

She waived a preliminary hearing, allowing the case to proceed to a county court.

Prosecutors say 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.

Joyce Mitchell  appears with her lawyer Stephen Johnston before Judge Buck Rogers in Plattsburgh City Court on June 15, 2015 in Plattsburgh, New York. (Photo by G.N. Miller - Pool/Getty Images)

Joyce Mitchell appears with her lawyer Stephen Johnston before Judge Buck Rogers in Plattsburgh City Court on June 15, 2015 in Plattsburgh, New York. (Photo by G.N. Miller – Pool/Getty Images)

A source told CBS News that Mitchell had sex multiple times with Matt inside the prison. She gave details of the encounters, sources said.

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CBS News reported that Wylie would not confirm a sexual relationship but said, “Obviously, Joyce Mitchell went a step a further as far as her relationship with these two individuals. Whether it’s showing them more attention than anyone else or them showing her attention or affection.”

Law enforcement sources also told CBS News there was an alleged agreement between Mitchell and the two men to kill her husband, Lyle.

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. That has led searchers to believe the men are still near the prison in Dannemora.

Lyle Mitchell visited his wife, Joyce in the county jail for about an hour Tuesday, Favro said. The couple communicated via telephone and were separated by a glass divider. Favro says he saw no sign of emotion from Joyce Mitchell, who is under constant monitoring.

Mitchell was charged Friday with also supplying a punch and a screwdriver to the two inmates. Her lawyer entered a not-guilty plea for her. 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.

 

The source said law enforcement is investigating to determine whether it was an attempt by the inmates to force her to help them and to keep her quiet about their escape plans or whether she had willingly plotted with them to kill her husband.

Authorities say 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.

Wylie says they apparently used tools stored by prison contractors, taking care to return them to their toolboxes after each night’s work.

Workers have welded shut three manholes, including the one from which the convicts climbed out.

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