The 500 pound World War Two device was picked up during dredging work.
Female Commander Of HMS Portland 'Removed From Post'
The first female commander of a frontline warship in the history of the Royal Navy who left her vessel last month amid claims she had an affair with a shipmate, has been removed from her post.
A spokesman for the Royal Navy confirmed that Commander Sarah West had been "removed from command'', but said she would remain in the service and be re-appointed to another post.
Cdr West, 42, took charge of Type 23 frigate HMS Portland in May 2012, but left her vessel in July when claims emerged that she had a relationship with a fellow sailor.
At the time the Royal Navy said it would conduct an inquiry into whether she breached the armed forces' code of social conduct, which governs personal relationships within the military.
In a statement a spokesman said no details would be given of the inquiry or its outcome.
"We can confirm that Commander Sarah West, Commanding Officer of HMS Portland, has been removed from Command,'' said the spokesman.
"This is an internal matter between the individual and her senior officers and we will not give further details of the removal.
"Commander West will continue to serve in the Royal Navy and she will be reappointed to a post where her skills and experience can be used to best effect.''
The spokesman added that Cdr West's second-in-command has taken over the running of the ship.
After her appointment two years ago Cdr West described it as the greatest achievement of her career, but in an interview earlier this year she explained how work commitments made it difficult to have a relationship.
She told the Daily Mirror:
"I'm really proud to be the first woman but I'm not reinventing the wheel. Lots of women in the services have challenging roles. It's just that I happen to be newsworthy at the moment.
"There are drawbacks though. Years at sea probably explains why I'm single. But every person in the military makes sacrifices.''
Cdr West, born and raised in Lincolnshire, studied maths at the University of Hertfordshire before joining Britannia Royal Naval College in September 1995.
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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