MALONE, N.Y. (AP) -- A sheriff involved in the search for the surviving inmate who escaped from a northern New York prison three weeks ago says the convicted killer could have a tougher time eluding searchers without his partner.

Inmate David Sweat is still on the lam a day after fellow escapee Richard Matt was shot to death by officers.

Clinton County Sheriff David Favro says Sweat is likely fatigued and no longer has a partner to watch his back or act as a lookout while he rests.

Officers continued to focus Saturday on heavy woods 30 miles west of Clinton Correctional Facility as they looked for Sweat around the area where Matt was killed.

Favro says there is no evidence the pair had split up.

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