Dr Ashraf Marwan's memoirs could not be found after his death
A coroner in London has rejected suggestions of suicide or murder in the case of Egyptian billionaire Dr Ashraf Marwan, who was found dead in June 2007, after he fell from the balcony of his fourth-floor flat in central London.
Even after the conclusion of the inquest into his death, the question remains: did he jump or was he pushed?
Five years before his death, Dr Marwan had been exposed as a spy, possibly one of the most important in the recent history of the Middle East.
To the outside world, few people had more impeccable credentials than Dr Ashraf Marwan.
During a long and distinguished career, the Egyptian billionaire was a diplomat, businessman, minister and government advisor.
His wife of 40 years was Mona Nasser, daughter of former President Gamal Abdel Nasser.
But in 2002, historian Ahron Bregman exposed him as a spy.
To the Israelis, he was the double agent who tried to warn them about the onset of a surprise Egyptian attack in 1973 that became the Yom Kippur war.
Dr Marwan was correct about the day of the offensive, but not the time - which caused speculation later that he had deliberately misled Israel.
At the time of Dr Marwan's death in 2007, Ahron Bregman was helping the Egyptian with his own explosive memoirs.
"Dr Marwan was a master spy - he was involved with the Israelis since 1969," he says.
"In my view, he misled them - he worked for Egypt. He was involved with the Italians since 1971 and with the Americans since 1975.
"And if you go to the offices of MI6, and ask to talk to Tony and Jane - they are the handlers of Dr Marwan in the UK."
The manuscript of Dr Marwan's book has not been seen since his death on 27 June 2007.
As far as the businessman's family is concerned, the missing book is one of the strongest indications that he was murdered.
This week, an inquest in central London returned an open verdict on the death.
Dr William Dolman, the assistant deputy coroner for Westminster, said there was no evidence that Dr Marwan committed suicide.
Dr Dolman described Dr Marwan's demeanour in the days before his death as "normal and cheerful".
Dr Ashraf Marwan's family continue to believe he was murdered
"There is no evidence of mental or psychiatric disorder," he said, adding that there was "no evidence of any intention to commit suicide".
"It is clear that Dr Marwan had a great deal to be worried about and was stressed."
The threat of assassination played heavily on Dr Marwan's mind, claims Ahron Bregman, who spoke often to the Egyptian before his death.
"He mentioned at least twice to me that he was afraid and concerned about assassination," he says.
"He even mentioned Mossad, and I said to him at the time, and I still believe now, that it is not in the interests of an organisation like Mossad to assassinate him because it would make it more difficult to recruit more spies."
The coroner found no evidence of Mossad involvement or indeed, murder.
Two witnesses, both former business associates of Dr Marwan, told the inquest that they had seen the businessman step to his death from his balcony.
Dr Marwan was 63 when he died and had a history of heart disease.
I am happy because the worst thing in Egypt is to be labelled as someone who took your own life
Mona Nasser, Wife
One of his friends, Hamdy El-Sawy, told the BBC after the inquest that he believed it was an accidental death.
But Ahron Bregman believes he was murdered, as does the Egyptian's family.
Dr Marwan's widow, Mona Gamal Abdel Nasser welcomed the open verdict.
"I am happy because the worst thing in Egypt is to be labelled as someone who took your own life," she said.
"My husband was a brave man who worked for his country. He was a risk taker but he would never take his own life.
"He wanted to live; he loved life. He was a good and generous man. It was such a crime and so cruel to deprive him of his life in such a cruel way.
"I wasn't there when it happened but I'm certain someone came in and just threw him over the balcony. He was very frail and could easily have been carried and thrown from the balcony."
The family have criticised the Metropolitan Police investigation into the mysterious death and have claimed that vital evidence, such as the shoes Dr Marwan wore at the time of his death, have gone missing.
They have vowed to continue their search for the truth.
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