The 37-year-od had been walking solo in the mountains near the Spanish and French border and was last seen on 22 November last year.
The charity said it would make no further announcement until further details were confirmed, adding developments “may take days or even weeks”.
It comes after the Daily Mirror reported Spanish police sources had said “human bones” were found on Friday near where the Durham woman disappeared.
The paper also quoted French police chief Jean Marc Bordinaro as saying: “We cannot say anything at the moment because the discovery of the bones is too recent and they must be properly analysed.”
Esther Dingley: Partner informed of remains find in Pyrenees
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Bones found near area where missing British hiker Esther Dingley disappeared
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Police searching for missing British hiker Esther Dingley find bones near site of last contact
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