Offers of help came the New York Police Department and the U.S. Department of Homeland Security as officials continued searching for two missing, Montana State Prison inmates, one accused of bilking television personality David Letterman.

Sunday marked the third day of the Deer Lodge Valley search launched after staff determined Kelly A. Frank, 45, and William J. Willcutt, 22, were missing from the prison ranch. New information indicated the pair "may be armed and have other provisions to sustain themselves," according to a prison news release. Warden Mike Mahoney, contacted Sunday at the prison in Deer Lodge, declined to provide specifics.

Officials said Frank and Willcutt fled in a truck Friday while working at the prison ranch.

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Frank was arrested in 2005 on allegations he crafted a plan to kidnap the son of Letterman, who has a ranch near Choteau. 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. Willcutt has been convicted of burglary.

The New York Police Department's offer of help was declined because of "the logistical complications of bringing folks from the East Coast," Mahoney said. He said a detective with NYPD's threat-assessment unit had been in touch and "I can only assume it would be in connection with Mr. Letterman."

Mahoney also said cloudy conditions prevented use of Homeland Security helicopters as part of the search Sunday. The search involved a prison dog and people trained in "man tracking," he said.

The search continued to focus on an area where the ranch's 1965 truck was recovered. Mahoney said the site is in the mountains south of Deer Lodge.

Frank and Willcutt were assigned to a ranch crew that moves irrigation pipe. A supervisor noticed Willcutt and the truck were missing Friday afternoon, and a count of inmates revealed Frank was gone, as well. The half-ton truck was found at about 5:30 p.m. Friday.

Willcutt lived in a prison work dormitory. Frank lived within the prison.

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