The 500 pound World War Two device was picked up during dredging work.
Lapland Brothers' Convictions Overturned
Two brothers jailed after being accused of conning thousands of customers into visiting what they claimed was a Lapland-style theme park had their convictions overturned by appeal judges.
Three judges at the Court of Appeal - who heard argument that the jury hearing the case should have been discharged after it was revealed that one of the panel had been exchanging text messages with her fiance - announced that they had ''reached the conclusion that the convictions are unsafe''.
Victor Mears, 67, and Henry Mears, 60, were jailed for 13 months in March this year and have both now served their sentences.
Bristol Crown Court heard during their trial that they offered visitors to the Lapland New Forest attraction in 2008 a winter wonderland with snow-covered log cabins, a nativity scene, husky dogs, polar bears and other animals, as well as a bustling Christmas market.
But families found a muddy field, a broken ice rink and fairy lights hung from trees, the court heard.
Dorset Trading Standards prosecuted the brothers under consumer protection laws.
Victor, of Selsfield Drive, and Henry, of Coombe Road, both Brighton, East Sussex, denied eight charges of misleading advertising but they were found guilty on all counts by the jury.
Their conviction appeals were allowed by Lord Justice Moore-Bick, Mr Justice Butterfield and Mr Justice Irwin.
No application was made for a re-trial.
Lord Justice Moore-Bick announced at the end of a hearing in London:
''We have reached the conclusion that the convictions are unsafe.''
He said the court would give its reasons for its decision at a later date.
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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