Mystery surrounds the death of a Coulsdon backpacker who disappeared in Goa after flying to India to scatter his mother's ashes.

The badly decomposed body of James Durkin, 34, washed up on a beach in the city of Canacona on March 8 this year, three weeks after he vanished.

The former Whitgift School pupil was last seen on February 15 by Indian police officers after he started a fight with a beach worker, an inquest at Croydon Coroner's Court heard today.

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The carpenter's disappearance, reported by a fellow traveller three days later, sparked an international investigation involving Interpol, Indian detectives and the Metropolitan Police.

His body, missing parts of his arms and legs, was spotted by locals at Dawalkhajan beach.

It was so badly decomposed he could only be identified by a distinctive tattoo and a post-mortem examination failed to establish a cause of death. 

Senior coroner Selena Lynch, recording an open conclusion this morning, said: "Has he come to some sort of harm at the hands of a third party or has there been an accident? I just don't know."

Mr Durkin, who grew up in Croydon but lived in Hackney at the time of his death, flew to Mumbai on December 28 to scatter his mother's ashes.

He planned to return in early February after travelling around India by motorbike with his friend Alexis Herodotou but changed his flight to extend his stay until March.

In a written statement, Mr Herodotou - a professional DJ under the name Alexis Raphael - told the court Mr Durkin had been "acting strangely" during the trip but had calmed down and was "feeling good" in the days before his disappearance.

But on February 15 Mr Durkin began behaving erratically again and kicked down the door to a beach hut in the Sea View resort of Canacona. 

Kim Gaber, a friend of Mr Durkin who was in the bar where he had earlier been drinking, said in written evidence to the inquest: "I saw Alex on the beach. Alex said [James] had lost his head. 

"It was then that James kicked the door down, thinking there was someone overdosing in the hut. He was clearly delusional.

"I have worked with people who have mental illnesses and thought it was more of a mental thing than drink or drugs."

Ms Lynch said she believed Mr Durkin, may have suffered a breakdown a "drug-induced psychosis" after taking MDMA a day earlier.

Mr Durkin agreed to drive to a cash machine with a beach worker to withdraw 3,500 rupees to pay for the repair of the door. But after reaching the cash machine he started a fight with the worker and fled, the court heard.

He later arrived at friend's house, where he collapsed. 

Mr Durkin was taken to hospital but refused treatment and police were called to help staff administer a drug, the inquest heard.

Officers later dropped him off near Colomb Beach, where he told them he was staying. 

There were no further reported sightings of him until his body was found three or four miles away. It is thought his body had been carried by the tide and spent up to three weeks floating in the Arabian Sea.

His father, James Durkin senior, identified his son's body having flown to India to search for him.

Addressing him and six of the younger Mr Durkin's friends during the inquest, the coroner said: "I'm so sorry for your loss. It causes the most awful would to lose a child or a friend in unknown circumstances.

"He was obviously a very popular guy and had lots of friends and I hope that you remember him in those happy days, enjoying his time out in India with his friends."

Detectives in India and from Interpol are continuing to investigate Mr Durkin's death.