A FRIEND of a missing Oxford flautist has urged people to keep looking out for her almost a month after she disappeared.

Maja O'Brien, 78, went missing after leaving her home in Wytham Street on the morning of Thursday, March 28.

Carole Thorn, who became friends with Ms O'Brien as her cleaner, said: "It's very upsetting - I saw her the day before she disappeared and she was very happy with everything in her life.

"It's really sad, not understanding what has happened. I don't understand why nothing has been found, like her bike - somebody doesn't just disappear."

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Police officers believe Ms O'Brien had her purple bicycle with her when she went missing, as well as her distinctive flute.

It is thought she was wearing an olive green coloured jacket, a red tracksuit and walking boots.

Ms Thorn said her friend bumped her head on the Tuesday, and fears she could have left home in a confused state.

Police had arrested a 45-year-old man on suspicion of robbery, in connection with the investigation, following reports of a man trying to sell a flute in Oxford.

However, officers established that it was not Ms O'Brien's flute and the man was released without charge.

Officers have concentrated enquiries in the area of Wytham Street and Hinksey Stream, handing out posters to residents, but Ms Thorn said she wanted the search to be broadened.

She added: "Maja could be anywhere - she could have got confused and rode off somewhere.

"I have to be positive that maybe she has gone off somewhere and she is still alive."

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A Thames Valley Police spokesman said enquiries into Ms O’Brien’s whereabouts are ongoing and encouraged members of the public to come forward if they know or see anything that could help.

The force previously described its search for Ms O'Brien as 'extensive' and said officers have been working alongside Oxfordshire Lowland Search and Rescue to locate her.

Ms O'Brien is around 5ft 6ins tall, of average build, with short grey hair and brown eyes.

Appealing to members of the public, Ms Thorn said: "People don't just disappear.

"I just want to plead to people to really think if they have seen her, or her bike lying around."

Anyone who can help can call 101 quoting reference 1528 (28/3).