Inspector Bob Jacobs said: "I understand that Sara can be easily confused and her family are understandably concerned that she may come to some harm.
“I believe that it’s likely that Sara is still in the Beaminster area. She is reasonably fit for her age and she has been known to walk considerable distances.”
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Wednesday morning's weather for the east of the region
Wednesday morning's weather for the west of the region
A mobile DNA screening unit has been set up in a village where detectives are working to find a grandmother's killer.