A four-day police search for a missing 76-year-old woman has worried folk in an Oxfordshire town.

Thames Valley Police is still looking for Iona, whose surname has not been disclosed, after she disappeared from Witney on Monday morning (February 12).

Drones and helicopters have been searching the River Windrush after a person was spotted in the water.

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The force said it was growing “increasingly concerned” as it continues to be stumped by Iona’s whereabouts.

Oxford Mail: Missing Iona was last seen in Witney on MondayMissing Iona was last seen in Witney on Monday (Image: TVP)

Witney residents have questioned why police have not found the elderly woman after more than 72 hours.

One woman, who asked not to be named, told the Oxford Mail: “With all the ambulances and fire bridge trucks and helicopters, you would hope they would have found something by now.

“People have been speaking about it for days. I have got two walking groups and everyone has been asking about her.

“I really hope she’s Ok.”

Oxford Mail: Police by the river in WitneyPolice by the river in Witney (Image: Police)

The search had initially focused on the stretch of river near the Windrush Leisure Centre in Witan Way.

A person was reported to have entered the water on Monday – prompting a major response from the emergency services.

One man, who lives near the river, said: “It’s very treacherous down by the river. I rarely walk down there myself.”

Another woman from Witney added: “I normally walk in daylight with someone else, but it is still worrying to think about.

“The river is so fast flowing and the mud is right at the top. You would think if someone fell down then they might get stuck.  

“It’s so tragic.”

Homeowners near the leisure centre said they hadn’t seen any emergency services since Monday.

And there was no sign of the search operation when the Oxford Mail visited the area this morning.

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Detective inspector Rob Platt said: “As part of our enquiries searches were conducted at the River Windrush in Witney.

"However we are keeping an open mind and following all lines of enquiry."

Oxford Mail: The River Windrush in Witney was described as 'treacherous by one residentThe River Windrush in Witney was described as 'treacherous by one resident (Image: Oxford Mail)

Police spokeswoman Lottie Walker confirmed today (Thursday) that searches were ongoing for Iona.

She provided no further updates.

Police described Iona, whose last name has not been revealed, as 5ft 6in tall and of slim build.

She was last sighted in Witney, where she lived, at 11am on Monday.

At the time, she was wearing a brown three-quarter length coat with fur around the hood, leggings and black Nike trainers.

Oxfordshire Fire and Rescue Service and National Police Air Service have also been involved in the search.

Police have urged anyone with information to call 999 or visit the force's website, quoting the reference number 43240068765.