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."
More top news
A review of one of Hampshire's longest unsolved murder investigations has led police to take the unusual step of naming two suspects.
In a report published today, the Transport Select Committee says Government should not proceed with 'All lane running' schemes.
Thursday morning's weather for the west of the region