The 500 pound World War Two device was picked up during dredging work.
Schizophrenic Jailed For Beheading Flatmate In Bournemouth
A paranoid schizophrenic who killed his flatmate in Bournemouth and cut off his head after suffering from delusions he was being persecuted has been jailed for life.
Karl Addo will serve a minimum of six and half years for the killing of Sergio Marquez but may never be released from Broadmoor because he is so ill.
The 30-year-old had suffered years of mental illness which led to the extreme complex that he was being assaulted by gangs with special powers and been injected with drugs.
He believed that Spanish waiter Mr Marquez, 23, was part of a gang and that he wanted to kill and torture him.
Fearing for his life, Addo snapped on the day he had been told to leave the flat in Lansdowne and brutally killed Mr Marquez.
He hit him with a cleaver and stabbed him in what was a "prolonged horrific and very violent attack and his body was terribly mutilated,'' Nigel Pascoe QC, prosecuting told Bournemouth Crown Court.
Several doctors assessed Addo as being profoundly mentally ill and borderline insane. He mutilated the body of Mr Marquez to stop him recovering from his injuries, the court heard.
Sentencing Addo, Mr Justice Burnett told him it was common ground that he was dangerous.
He explained that Addo would serve the minimum term but he also imposed an indefinite restriction under the Mental Health Act.
"The result of the sentence I have imposed is that the public now has the double protection provided by the Mental Health Act and the involvement of the parole board,'' he said.
"You will be detained for at least six and half years but will not be released unless the relevant authorities conclude that is it safe to do so.
"Given all that I have heard, you must recognise that there is a real possibility that such a conclusion will never be reached.''
Engineering graduate Addo, who was born in the UK but had also lived in the US, absconded from the Huntley Mental Health Centre in London where he was a voluntary patient the day before a mental health tribunal in October 2011 decided he should be sectioned.
Addo then "disappeared'' from mental health services before he moved to Bournemouth in May 2012. He killed Mr Marquez, a hotel waiter, on July 17 last year - nine months later, the court previously heard.
The headless body of Mr Marquez, which had also been eviscerated, was found by other flat mates who ran screaming from the flat.
Police officers arrested Addo nearby covered in blood, the court was told. He had fled the flat when the others had returned.
Flatmates told police that Addo had been acting strangely, that he used to steal food from them and had used book pages as toilet paper. He had not paid his rent and had been told to leave by the landlord, the court heard.
Mr Marquez had sent a note about his anti-social behaviour and Addo resented it, the court heard.
Court Hears Of 'Brutal' Killing
The victim had tried to defend himself from the attack but was cornered in a room. A neighbour heard some of the attack and Mr Marquez saying "please Karl, please Karl'', furniture being dragged around and then Addo laugh, Mr Pascoe said.
He was decapitated and disemboweled after he died, the court was told.
Addo, of no fixed abode pleaded not guilty to murder on Monday but guilty to manslaughter through diminished responsibility.
The prosecution said the plea was acceptable because Addo had been severely mentally ill when he killed Mr Marquez, who lived in Coin near Malaga in Spain and had come to England to find work.
The judge paid tribute to Mr Marquez. "He was a bright 23-year-old Spaniard who was living and working in Bournemouth. In particular, he wished to improve his English and so his general prospects, not least because of the very difficult economic position in Spain in recent years.
"The brutal killing of this young man has had a profound and lasting impact upon his mother and family.''
Speaking after the case, Mr Marquez's mother Maria Carmen Marquez Torres said:
"Sergio was a kind, good-hearted and beautiful man who touched the lives of everyone who met him.
"I have lost my son and the world has lost a wonderful man.
"I believe that I have received justice for me and for Sergio.
"No sentence would ever be sufficient and nothing will ever compensate me for the loss of my son, but I find comfort in the fact that Mr Addo will not have his freedom for a long time and inflict this pain on any other family.''
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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