Authorities say a weekend theft in Clancy may have been committed by a convicted burglar who escaped from the Montana State Prison on Friday with a man who was once accused of plotting to kidnap David Letterman's son.

Employees at the Clancy Store told authorities a man they believed to be William J. Willcutt, 22, stole three knives, a box of .38 caliber ammunition and food from the store at about noon Sunday, the Jefferson County Sheriff's Office said Monday in a news release.

The employees contacted law enforcement hours after the man left, once they realized who he was, the release said.

Law enforcement officials have determined there is a "good possibility that this individual was, in fact, William Willcutt," the release said. "It has not been 100 percent confirmed that Willcutt was in the Clancy area; however, deputies have been coming the area for signs or other sightings."

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Willcutt is familiar with the Clancy area from several burglaries he committed there in 2005, the release said.

On Monday, prison officials used a helicopter to search for Willcutt and Kelly A. Frank, 45, who fled from a ranch operated by the prison in a prison work truck. Other potential sightings were reported in Powell, Lake and Broadwater counties, but they had not been confirmed Monday night, prison officials said.

Letterman's publicist would not say whether Friday's prison break would change any plans Letterman may have had for time at his 2,700-acre Montana ranch near Choteau, about a three-hour drive north of the prison.

"I never comment on David's private life," said Tom Keaney, spokesman for Letterman's production company.

Authorities began looking for Frank and Willcutt the day they disappeared. The search grew more tense with indications the two may have acquired a weapon.

Frank was arrested in 2005 on allegations he crafted a plan to kidnap Letterman's son and the boy's nanny for a $5 million ransom.

A charge of solicitation to kidnap was dropped in return for pleas of guilty to other charges, including felony theft and misdemeanor obstruction. Frank worked as a painter at Letterman's ranch and received a 10-year prison sentence for overcharging him. At the time of his arrest, Frank was on supervised release for a 1998 conviction for stalking and intimidating a woman.

Willcutt has been convicted of burglary.

Warden Mike Mahoney said it appears someone stashed provisions, possibly weapons, for Frank and Willcutt.

The warden said the federal Department of Homeland Security provided a Black Hawk helicopter for the search, and about 15 people on the ground Monday searched mountainous terrain south of Deer Lodge.

The ground team used all-terrain vehicles and was assisted by a dog, but it was unable to confirm a reported sighting in the area, according to a prison news release issued Monday night.

The helicopter returned to its base at 2:30 p.m.

The prison search team transitioned into a scaled-back "observation team" and planned to work throughout the night, the release said.

Frank's link to Letterman has brought increased focus to the escape. Mahoney had declined offers of help from the New York Police Department.

Teton County officials said they would not comment on whether they have done anything to increase policing around Letterman's ranch.

"We don't know of any reason he (Frank) would come back up here," said County Attorney Joe Coble. "Unless we get some indication he is here, or coming this way, it doesn't really affect our operation."

The two inmates were working on the prison ranch that operates as part of a program to rehabilitate criminals. Frank and Willcutt were on a crew that moves irrigation pipe. Officials believe they took off Friday afternoon in the ranch's 1965 pickup truck, which was recovered within hours.

Willcutt, who had a parole hearing earlier this year, lived in a prison work dormitory. Frank, who would have been eligible for parole in three months, lived within the prison.

A state lawmaker who oversees Department of Corrections issues said he spoke to the warden and concluded the prison's normal operating procedures had been followed in the time preceding the escapes. It appears Frank and Willcutt "just decided to hightail it," said Sen. Steve Gallus, D-Butte.

Gallus said the prison may need to re-evaluate the screening used to determine whether inmates are suited for work outside the prison walls.

"It really gives everyone a black eye when one or two of those inmates takes advantage of being outside of the perimeter," the legislator said.

The most recent escape from the prison was in 2003 and the most recent escape from the ranch in 2001, prison officials said. In both cases, the men were caught in about 24 hours.

Use of prison vehicles in escapes is not new, having occurred at least eight times over the last dozen years. One man never caught by prison officials, convicted murderer Philip Sadowski, fled in 1996 by using a pickup truck assigned to a prison logging crew.

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