The Benton County Sheriff's Department is looking for 72-year-old Hellen Erlene Cook.
Cook is a white female, 5 feet tall, 97 pounds, has brown hair and blue eyes.
She was last seen about 11:30 a.m. Saturday at her lake property she and her husband owned southwest of Warsaw close to Truman Lake. The Benton County Sheriff's Department said Cook walked away while her husband was mowing the lawn.
Cook was wearing a white T-shirt, blue jean shorts, tennis shoes and was carrying a walking stick.
Cook suffers from Alzheimer's disease.
She is known to frequent McDonald's restaurants and Walmart.
The Benton County Sheriff's Department said Cook may be on her way to Buckner, Mo., where she lives.
Anyone who sees the missing person, suspect, associate or vehicle, or anyone with information about Cook's whereabouts is urged to call 911 or the Benton County Sheriff's Department at 660-438-9555.