The 500 pound World War Two device was picked up during dredging work.
Latest On Search For Damien Nettles' Body
Police investigating the suspected murder of a 16-year-old boy who went missing 15 years ago have concluded their latest search for his body.
A man and woman who were arrested in connection with the case of Damien Nettles, of Woodvale Road, Gurnard, Cowes, Isle of Wight, who went missing on November 2 1996, have also been released on police bail.
Hampshire Police said a search for his body and other evidence at an address in Marsh Road, Gurnard, finished on Wednesday 2nd November with no evidence or human remains being found.
A 35-year-old woman and a 44-year-old man, both from Cowes, who were arrested on suspicion of conspiracy to commit murder, have now been bailed until November 16, pending further inquiries.
Earlier this year, five other men were arrested and bailed in connection with the murder.
Officers also carried out a search for Damien's body at Dodnor Nature Reserve, near Newport, but nothing was found.
The address in Marsh Road was sealed off on Tuesday by staff from the force's major crime department who worked alongside a dog support unit, scientific services department and the Island Support Unit (ISU).
A fingertip search of the property was carried out and the ground surveyed inside and outside the address, while the back garden was excavated and victim recovery dogs used.
Senior investigating officer, Superintendent David Powell, said: ''We are disappointed that Damien has not been found yet, but this search was necessary to allow a thorough assessment of information about the Marsh Road property to be completed.
''As a result, police are confident that Damien's body is not at the address.
''I've phoned Damien's mother Valerie to speak with her about the outcome of the search at Marsh Road and the status of the two suspects arrested.
''We remain grateful to the Nettles family for continuing their campaign to maintain awareness and encourage new leads.''
The disappearance of Damien, following a night out with friends, has been kept in the spotlight by his family over the years.
His mother Valerie, 58, who now lives near Dallas in Texas, and his brother and two sisters have ceaselessly campaigned to find out what happened to him.
Speaking from the United States, secretary Mrs Nettles said earlier this year she was ''cautiously optimistic'' about the previous arrests but she was prepared for it to come to nothing.
''I have always felt that something bad happened to Damien that night. It's just a shock we are here and now and this is being looked at. I'm hoping that we will get a result,'' she said.
Anyone with information about the Damien Nettles case can contact Hampshire Constabulary by phoning 101 or emailing email@example.com
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The 79-year-old man suffered a serious head injury in the Cranmer Road car park in Winton.
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