A search is continuing for a missing woman who disappeared nearly three weeks ago.

Iona, 76, whose surname has not been released, was last seen in Witney town centre on Monday, February 12.

Lowland Rescue Oxfordshire, a team of professional volunteers who support the police in searching for high risk vulnerable missing people, deployed a Water Unit, Drone Unit and personnel to search river banks from 6am yesterday (Sunday, March 4).

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Following her disappearance police divers took part in a major search operation of 2km of the River Windrush and a specialist dive team from Avon and Somerset were brought in.

A spokesman for Thames Valley Police confirmed on Thursday (February 29) that the Avon and Somerset team are no longer involved but other organisations are continuing to search the river.

Chief Inspector James Sullivan said police were "extremely concerned" for Iona's welfare but were "keeping an open mind and following all lines of enquiry".

Anyone who has any information that may assist the investigation should call the emergency number 999, quoting the reference number 43240068765.

Any sightings or information on Iona's whereabouts can be reported on the Thames Valley Police website. 

Police guidance states you will not be wasting police time by reporting someone as missing. 

It also states that a missing person will not be in trouble with the police.