Hampshire Constabulary says a woman pulled from the water at Southsea yesterday (Saturday) has died.
The police force also says it does not believe a hovercraft, landing at the time of the incident, was to blame.
Hampshire Constabulary said: "We were called shortly after 5.45pm, on Saturday April 24, to a report that a woman was unconscious in the water, off Clarence Esplanade, Southsea.
"Officers attended and a 59-year-old woman was taken to Queen Alexandra Hospital.
"Despite best efforts, she was sadly pronounced dead on Saturday evening."
The woman's next of kin have been informed and are being supported by officers.
Her death is not being treated as suspicious.
She was brought out of the water and taken to Old Portsmouth, by the crew of Gosport and Fareham Inshore Rescue Service, before being transported to Queen Alexandra Hospital in Portsmouth.
The woman was initially thought to be aged in her 40s, after a statement from the ambulance service.
Hovertravel issued a statement yesterday (Saturday), to say the pilot of the Solent Flyer, which was landing at the time of the incident, had been informed and protocol was followed.
A Hovertravel spokesperson said: "Contrary to various media reports, we can confirm the Solent Flyer was not involved with the incident involving a body in water — but the crew were alerted."
Police have also confirmed that they do not believe a hovercraft was involved.
Read Hovertravel's statement in full:
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