Detective Chief Inspector Ian Pollard from the Surrey and Sussex Major Crime Team, who is leading the investigation, said: "While initially it was thought that we were dealing with a sudden death, officers became increasingly suspicious of the circumstances.
"As yet, the cause of her death is unexplained and we are awaiting the results of a post mortem that will take place on Tuesday.
"However, our enquiries lead us to believe that this was not a natural death and a murder enquiry has been launched."
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Holly has the lunchtime forecast for the west of the ITV Meridian region.
Holly has the lunchtime forecast for the east of the ITV Meridian region.
Holly with Tuesday morning's weather in the west