Mystery still surrounds the death of an alcoholic boatman whose body was found in the Oxford canal last summer.

Oxfordshire coroner Nicholas Gardiner recorded an open verdict at an inquest into the death of William O’Neill, saying he could not “exclude something more sinister” than that he had simply fallen into the canal.

The inquest heard Mr O’Neill, 62, known as Nemo, went missing on July 6. His body was found in Castle Mill Stream, in Jericho, four days later.

The mechanical engineer had alcohol problems most of his life and at times was drinking a bottle of vodka a day.

Divorced Mr O’Neill, originally from Dublin, lived on a boat named Notre Dame, moored near Combe Road in Jericho, and had been having hallucinations in the days leading up to his death.

He also had a history of falling into the canal. His daughter Zoe O’Neill, of Upway Road, Oxford, told the hearing her father was very happy and content.

She said: “He told me about the hallucinations a couple of weeks before, but when I went down to see him he was laughing about it.”

A post mortem showed he had a very low level of alcohol in his body and there were no injuries to suggest an assault.

In a statement, friend and neighbour Mark Dawson, of Castle Mill Stream, said he had reported Mr O’Neill missing.

On the Saturday night before Mr O’Neill disappeared, he apparently invited two men, already believed to be drunk, on board his boat.

They were seen drinking together and in the early hours woke Mr Dawson by being rowdy.

Mr Dawson said: “Nemo had become delusional and often said he saw people in the trees or saw people around the boat. He thought a plastic bag was a cat.

“I didn’t know whether to phone an ambulance because of the delusions or the police because they were being rowdy.”

A 40-year-old man was arrested on suspicion of murder, but was released without charge.

Police said Mr O’Neill’s death, by drowning, was no longer being investigated. Mr Gardiner said how he came to be in the canal was unknown.

He added: "He had been known to have hallucinations in the past.

"His blood alcohol was virtually zero; in a person accustomed to drink they can suffer pretty bad hallucinations.

“He was possibly unable to control himself, had some sort of fit and fell in.

"An alternative explanation is more sinister, in that someone was instrumental in his going into the canal. I cannot exclude something more sinister.”

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