IRVINGTON, N.Y. (CBS 2) — A baffling mystery in Westchester County has police and relatives are rethinking what might have happened to an elderly woman, who vanished without a trace.

Irvington Police Chief Michael Cerone and his lieutenant descended the steep slope on the west bank of the Saw Mill River, scanning for signs of 84-year-old Betty Iannarelli. The search has now entered its 17th day.

“It’s driving me personally insane basically. She has vanished basically into thin air from our perspective. There’s no sighting, there’s no other leads,” Cerone told CBS 2’s Lou Young.

The Alzheimer’s patient wandered past a security camera in Irvington two hours before being reported missing on August 5th. The search began immediately with no success.

Debbie Iannarelli, the missing woman’s daughter, keeps a candle burning for her lost mother and a Facebook page sorting tips and theories.

Although the dogs brought searchers into the woods near the reservoir and aqueduct in the town, the woman’s family now believes something else must have happened.

“I believe someone picked her up,” Iannarelli said.

“In 20 years of being a cop — usually an Alzheimer’s patient will disappear, usually a couple hours, a day at the most. Now, we’re up to 17 days,” Irvington Lt. Michael Morano said. “We’re just searching everywhere.”

There has been no scent of a body and no call from someone who found a woman wearing an Alzheimer’s ID bracelet.

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