Some see it as paradise: a beautiful stretch of sandy beaches where drugs are plentiful and living is cheap. But the chances are that there will soon be a reduction in the number of British tourists travelling to Goa, on the west coast of India. Few can now be unaware that a succession of unexplained deaths is revealing a deeply sinister side to the popular resort.

Some 40 Britons died in Goa last year, a tally of which the local police are understandably not proud. But the families of those who died in mysterious circumstances believe that local cynicism about western drinking and drug-taking means that some cases are closed too readily. Evidence is sometimes overlooked, even where a crime has clearly been committed.

Last month, for instance, the battered, half-naked body of Scarlett Keeling, 15, was found on a Goan beach. The police initially told her mother that she had drowned, but dogged investigation by her family and friends has shown that she is very likely to have been raped and murdered.

Scarlett’s shorts and pants had been removed and her bra top pushed up around her neck. There was not enough water in her lungs to be fatal and although she had definitely had sex, it was impossible to say whether it was consensual.

“Without doubt they [the authorities] are trying to cover things up,” said Fiona MacKeown, Scarlett’s mother. “I have viewed my daughter’s body. The police said there were no abrasions and her body is covered in them. They say she drowned in shallow water but she was a strong swimmer.”

The difficulty that Scarlett’s family have had in determining what happened comes as no surprise to Amanda Merritt, whose brother Stephen Bennett, a 40-year-old father of two from Cheltenham, was found hanging from a mango tree in December 2006.

After a year of trying to piece together what had happened to her brother, Merritt has recently succeeded in persuading the Indian police to reinvestigate his death. At first – like Scarlett – he was dismissed as just another hedonistic tourist. But Merritt believes he was targeted and killed by members of Goa’s criminal underworld.

Stephen, who had travelled alone in Asia several times as part of a masters degree in Chinese theatre studies, had been taking a December holiday alone in Goa and intended to be away for two weeks. He planned to spend Christmas with his two daughters and had already wrapped their presents.

On December 12 his body was found hanging from a tree, a woman’s sari around his neck, in a village 200 miles from Goa. His death was initially portrayed as a drug-induced suicide. The police later suggested he was a promiscuous homosexual who had come to India for sex, and branded him a notorious drug dealer, even though he had been in Goa less than a week and it was his first visit to India.

“Every day there was a new ridiculous claim,” says Merritt, 45. “But every one was a lie. I saw Stephen two days before he left. He was his usual chirpy self. He had everything to live for – two great kids, a new girlfriend, a successful career and supportive family and friends. Yes, he’d smoked the odd joint in his time, but that was it. He was a regular British guy.” After a postmortem examination revealed a fractured skull and severe beating to his body, a new story emerged. A 25-year-old woman from the village where his body was found came forward to say Stephen had made a pass at her. She had told her husband and he had reacted furiously, rounding up five other villagers and beating Stephen to death before hanging him in an “honour killing” to preserve her dignity.

The six men were arrested, confessed and were placed in police custody, but later retracted their statements. Meanwhile, in Britain, disturbing details came to light. Stephen’s mother insisted that he had called her from Goa on December 6 saying he was terrified because he was being followed.

He told her three men had broken into his room and threatened him during the night. He had blacked out and woken up the following morning in a backstreet, with a severe headache. He believed he had been drugged.

“He was quite obviously shaken. Mum suggested he check himself into one of the large western hotels, get on the internet and book a flight home from Mumbai airport because there were no flights out of Goa,” Merritt says.

How he ended up in the village of Malsai in Roha, more than 70 miles from Mumbai, remains a mystery. It is accessible only up a two-mile dirt track. What his sister has discovered is that Stephen left Goa on December 7 in a taxi with two local men. In the first of two calls to his mother later that day he said he was sharing a taxi to Mumbai. But in the second call he sounded agitated.

“He said he was worried about the two men in the taxi,” Merritt says. “He said he knew they were something to do with what had happened to him in Goa.”

Five days later his battered body was found hanging from the tree. A postmortem revealed that he had been dead for some time before being hanged: £500 in cash, a digital camera and his mobile phone were missing.

While the police have so far obstinately stuck to their original “honour killing” theory, Merritt has statements from Goan sources claiming that the men Stephen travelled with were directly linked to violent attacks on other western tourists and connected to the Goan criminal underworld. Stephen was by all accounts a little naive – perfect prey.

All of which gives the lie to Goa’s reputation as a laid-back, idyllic holiday destination. According to expats living there, it’s not unusual for westerners to “disappear” – posters for “missing” people are a frequent sight throughout the city. Nor is it uncommon to hear stories about the abuse of Rohypnol and other date-rape tranquillisers.

Scarlett’s mother has been heavily criticised for leaving her 15-year-old daughter in the care of an Indian tour guide while the rest of the family went travelling around the neighbouring state of Karnataka. She was certainly unwise, yet was clearly unaware of Goa’s uglier side. Much of what goes on in the “travellers’ paradise” goes unreported. “The editor of a local paper told me that he had been ordered by a police representative not to report on my brother’s case at all,” Merritt says.

She has uncovered a number of intriguing links between the men who shared Stephen’s taxi and the village where he was killed. “It has given me some sense of closure, but a year on I’m beginning to realise my preoccupation with the investigation is a ploy to keep myself busy so I don’t have to deal with the pain of losing my brother in such a horrific way,” she says.

“There are days when I don’t want to get up, to eat, to speak to anyone. My personality is different. I used to be laid-back and patient, like Stephen, but now I cry more easily because my emotions are so much closer to the surface. I had always believed that human beings were inherently good, but the past year has destroyed my faith in human nature.”

The same painful journey awaits Scarlett’s mother, just embarking on her quest to discover what really caused her daughter’s death.

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