Man Who Plotted to Kidnap Letterman's Son Escapes from Prison

David Letterman's security team has been warned that the man who allegedly plotted to kidnap the talk show host's young son is on the loose and may have gotten hold of a gun, officials said yesterday.

Kelly Frank, 45, and a fellow convict escaped Friday from the Montana State Prison. They were last seen about 150 miles from Letterman's ranch, so .authorities don't think it's likely they headed back there.

But the local sheriff's office is keeping in close touch with Letterman's people until Frank is caught, said Mike Mahoney, warden of the Montana State Prison. "We have intelligence that leads us to believe these guys may be armed," Mahoney told the Daily News.