The 500 pound World War Two device was picked up during dredging work.
Teenager's Jaw Broken In Attack
An 18 year old has had his jaw broken after being punched in the face in Poole.
Detectives are appealing for witnesses and anyone with information to come forward after the man was assaulted in the town.
The incident, in which an 18-year-old Poole man was punched in the face by a man, happened along Hill Street, just off the High Street, at around 1.45pm on Thursday, 1 September 2011.
The victim sustained a fractured jaw and was treated at Poole Hospital.
Detective Constable Steve Sutton, of Bournemouth and Poole CID, said:
"This was an unprovoked attack that has left the victim with serious injuries.
"I am appealing for anyone who witnessed this assault, and anyone who has any information about the man responsible, to contact me as soon as possible."
The offender is white and aged around 20. He was wearing a blue polo shirt and tracksuit bottoms.
He had walked from the High Street into Hill Street with a group of other people, including a young woman, with blonde hair. She was wearing a blue tracksuit.
DC Sutton continued:
"Poole High Street and the surrounding area will have been busy at this time of the day and I believe that someone, perhaps several people, will be able to help me with this investigation.
"All calls will be treated in the strictest of confidence."
Witnesses and anyone with information should call Dorset Police in confidence on 01202 22 22 22 quoting incident number 01:313. Alternatively, call the free and anonymous Crimestoppers line on 0800 555 111 where mobile phone tariffs may apply.
640 men were killed when the South African troop carrier was hit by a cargo ship in 1917.
The 79-year-old man suffered a serious head injury in the Cranmer Road car park in Winton.
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