Arup Kalita's body was found this week, his skeletal remains finally recovered from the shallow depths a pond in the small village of Kukurmara in India's north-eastern fringes.

© UPEN/DEKA/BISWAJIT DASArup Kalita, left, and his belongings that were found with his remains
His mobile phone, motor bike keys, driving licence and trousers were all discovered along with his bones.

How he got there was no surprise to his grieving family. They knew the 29-year-old anti-corruption campaigner was dead when he disappeared in August last year. They had heard he had been beaten, tortured and then his corpse dumped into the pond where it was apparently trampled deep into the mud below by an elephant.

But what may be surprising to some is the location of his resting place - in the official grounds of Assam's forestry department.

His family and supporters say that location is the key. All believe he has paid the price for India's failure to tackle corruption at all levels.

Mr Kalita's apparent murder makes him the 18th anti-corruption crusader to be killed in India since 2008. Others include several campaigners who used Right to Information legislation to uncover corruption in government aid schemes for India's poorest, one of the country's leading crime reporters who exposed Mumbai's 'diesel mafia,' and a civil servant who was burned alive by oil smugglers.

Campaigners say the killing in Kukurmara, and the difficulty in getting it investigated, highlights the need now to create a powerful new watchdog to hold India's rich and powerful to account, from village officials to government ministers, on local and national levels.

Indeed even as Mr Kalita's body was being uncovered the Indian government was facing serious allegations of corruption in the award of mobile phone operator licences and contracts for last year's Delhi Commonwealth Games. One former minister is currently in jail, along with the head of the Commonwealth Games Organising committee and the daughter of the ruling Congress Party's main coalition partner.

The corruption Mr Kalita believed he had uncovered though, and which his family believe led to his death, was on an altogether smaller scale. But it did, in his view, threaten the forest environment in Assam's Kamrup West, where illegal logging is devastating the state's protected jungle.

Mr Kalita was a leader of the local All-Assam Non-Tribal Students Union which had been campaigning against local sand smugglers. The smugglers, who transport sand dug from a local river bed without paying taxes, were damaging local farmers' fields by spilling sand on crops and driving over planted plots.

His sister Manju Kalita Das told The Daily Telegraph he had visited the local Forest Department in August last year to complain about the sand-mining but was criticised by officials and local sand-diggers who were in the office.

"They said 'we also have stomachs and families to feed. We want this business to run, why are you making these complaints?' They feared they would lose their livelihoods."

His fellow student union leader Dhiren Mali, who was with him said he had been warned by a senior official of "grave consequences" if he did not abandon his complaints. "The official said 'I will teach you a lesson,'" he added.

Mr Mali said the union resolved to step up its campaign and a few days later received a tip that trucks of illegal timber were being covered with sand to smuggle them out of the district. They tracked the trucks as they headed towards the Kukurmara Forest Department office and raced ahead to urge officials to intercept them and arrest the drivers.

"The Forest officials said 'why have you come here?' Then they started hitting us, punching us in the head. I couldn't see Arup and when I was finally rescued by police they said Arup was OK," he said. He never saw his friend again.

Mr Kalita's cousin Pradip Kalita said he had been told by a police officer that they been unable to force their way in when they arrived on the scene but had heard Arup screaming and believed he had been tortured.

He said neighbours and forest dwellers nearby told him they had seen the department's elephant wading through the tiny pond stamping its feet shortly after the commotion and suspect it had been used to crush his body into the mud.

A spokesman for the Forest Department department declined to comment, but Police Superintendent A.J Buruah said an investigation is continuing and results of a post-mortem are pending. One forestry official has been arrested and four have absconded since the body was found.

He said some officials had claimed there had been a "scuffle" and Mr Kalita had slipped into the pond and drowned as he fled his assailants. "We'll find the cause of death, I want to give them [Mr Kalita's family] justice," he said.

The family has no doubt what and who caused their brother's death. "He has made so many accusations, so obviously they regarded him as an enemy," said his sister Manju. The family point out that it took a High Court order to force an investigation into the death and this was only carried out after a further demand.

Both family and supporters feel Mr Kalita's death is indicative of a failure to tackle corruption in India more widely.

Prashant Bhushan, one of India's top lawyers and anti-corruption campaigners, agreed. "It is a blue collar mafia and it is increasingly resorting to violence. It is bound to happen if you allow corruption to go unchecked, then the mafia resorts to violence against anti-corruption activists."

Her mother, who was too distraught to comment, wailed her son's name from her bed as her daughter listed their demands. They want £14,000 and a government job for one of their relatives as compensation. "And we want the culprits to be caught and given exemplary punishment," she added.

Former Chief Conservator of Forests M.C Malakar said Mr Kalita's complaints on corruption and official collusion in timber smuggling had some basis in fact. Illegal logging is destroying the state's forests, he said, and some officials had "joined the criminals."

"The situation here is volatile. There is an insurgency and criminals have taken advantage. It's difficult for our officials to go into the forest. There have been assault cases, and some officials might have joined the criminals. Timber has been stolen...officers have been suspended and action taken against them," he said.