A female employee at a New York state prison reportedly was questioned Sunday on suspicion of being an accomplice in the escape of two convicted murderers.

The New York Post said the employee, who is not a guard at the Clinton Correctional Facility in Dannemora, had already been removed from her post. It's not clear what her position at the prison was.

David Sweat, 34, and Richard Matt, 48, were still at large early Monday, having last been seen during a head count Friday evening. Sweat was serving a sentence of life without parole for the 2002 killing of a sheriff's deputy. Matt had been sentenced to 25 years to life for kidnapping, killing and dismembering his former boss in 1997.

New York State Gov. Andrew Cuomo said during a round of appearances on television morning news shows Monday that he'd be shocked if a prison guard was involved in the escape.

"We're going through the civilian employees and private contractors first," he said on NBC's "Today" show. "I'd be shocked if a correction guard was involved in this, but they definitely had help, otherwise, they couldn't have done this on their own, even from the equipment point of view."

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New York State Police has received over 300 leads in the investigation.

Maj. Charles E. Guess, commander of the New York State Police troop leading the search, told reporters Sunday that the men "could be literally anywhere."

Despite being described by a retired police captain who had investigated the 1997 murder as "the most vicious, evil person I’ve ever come across in 38 years as a police officer," the New York Post reported that women still find Matt attractive.

"He has a way with the ladies," one source told the newspaper.

Officials say the pair cut through the steel wall at the back of their cell, crawled down a catwalk, broke through a brick wall, cut their way into and out of a steam pipe, and then sliced through the chain and lock on a manhole cover outside the prison. On a cut steam pipe, the prisoners left a taunting note containing a crude Asian caricature and the words "Have a nice day."

Prison officials found the inmates' beds inside the facility stuffed with clothes on Saturday morning in an apparent attempt to fool guards making their rounds.

What isn't clear is how long it took Sweat and Matt to prepare for the escape, the kinds of tools used, what powered them, why no one heard the noise and how the prisoners hid the holes they made.

The New York Post reported that investigators believe the likeliest explanation is that Sweat and Matt had help. Cuomo said investigators were confident the men obtained the tools inside the prison. Acting Corrections Commissioner Anthony Annucci said an inventory of prison tools had so far shown none missing and he was in contact with contractors who were doing or had done work at the prison.

The New York Post reported that investigators believe the cuts made in the pipes were made by an experienced worker, with one source saying, "They are perfect, clean. That’s not normal — they had some help." The newspaper also reported that a number of contracting crews were carrying out work at the prison on a variety of projects.

Investigators told the Associated Press the men may have had assistance outside the prison, perhaps meeting up with someone who helped them leave the area, investigators said.

Investigators also were looking into a report made by a witness who spotted two men resembling the murderers in a backyard not far from the manhole where they emerged shortly after midnight Saturday. A man called out "Hey, what are you doing here?" before the other two took off, according to the New York Post.

On Sunday, Cuomo announced a $100,000 reward for information leading to the men's capture.

"These are killers. They are murderers," the governor said. "There's never been a question about the crimes they committed. They are now on the loose, and our first order of business is apprehending them."

"This is a crisis situation for the state," Cuomo continued. "These are dangerous men capable of committing grave crimes again."

Authorities set up roadblocks and brought in bloodhounds and helicopters in the search for the two men. Hundreds of law enforcement officers fanned out around the prison, about 20 miles south of the Canadian border, following up on dozens of tips.

Dubbed "Little Siberia" by locals, the prison houses nearly 3,000 inmates, guarded by about 1,400 correction officers. Surrounded by farmland and forests, the prison is only about a 45-minute drive by car to Montreal.

Martin Horn, former commissioner of the New York City Department of Correction and a professor at the John Jay College of Criminal Justice, told The Associated Press that prison breaks are not common.

"Prison escapes are a relatively rare event," said Horn, who is not involved in the probe of the Clinton escape. "That tells you that a great deal of planning is involved because it's not an easy thing to accomplish."

Horn, a former secretary of corrections for the state of Pennsylvania and a prison warden in New York state during the 1980s, said the two inmates had to "obtain some fairly sophisticated tools," either from the prison, which he said maintains an inventory of their tools — "every pair of scissors, every wrench, every power tool" — or from an outside contractor.

"Clinton is as secure a prison as you'll find anywhere in the United States," said Horn. "If it can happen at Clinton, it can happen anywhere."

Fox News' Ron Ralston and The Associated Press contributed to this report.