Police said that they have mapped the area of a remote Indian island where tribespeople were seen burying the body of an American adventurer and Christian missionary after allegedly killing him with arrows this month.

During their visit to the island’s surroundings on Friday, investigators also spotted four or five North Sentinel islanders moving in the area from a distance of about 500 metres from a boat and studied their behaviour for several hours, said Dependra Pathak, the director-general of police of the Andaman and Nicobar Islands, where North Sentinel is located.

“We have more or less identified the site and the area in general,” Mr Pathak said.

“They were patrolling the beach, at the same spot John was killed, with weapons,” he said, according to the New York Times.

“Had we approached ... they would have attacked. This case is the strangest and toughest in my life,” Mr Pathak said. “We are trying to enter into another civilization’s world.”

Indian authorities have been struggling to figure out how to recover the body of 26-year-old John Allen Chau, who was killed by North Sentinel islanders who apparently shot him with arrows and then buried his body on the beach.

Friday’s visit was the second boat expedition of the week by a team of police and officials from the forest department, tribal welfare department and coast guard, Mr Pathak said.

The officials took two of the seven people arrested for helping Chau get close to the island in an effort to determine his route and the circumstances of his death.

The fishermen who had taken Chau to the shore saw the tribespeople dragging and burying his body on the morning of November 17.

Chau’s family do not want authorities to seek justice for his death.

Chau approached the island in a kayak with the intention of bringing the word of God to the world’s oldest tribe.

The Sentinelese are thought to have lived on the island for 30,000 years but have had very little contact with outsiders.

North Sentinel island is part of the far flung Andaman Islands in the vast Bay of Bengal. The region is home to five Stone Age tribes — which anthropologists believe to be the last of their kind and are dwindling in numbers.

The family of Chau posted a statement to his Instagram account saying that they forgave the tribe reportedly responsible for his death.

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While the Sentinelese have been cut off from the rest of the world for decades they are a protected group under the government of India, which lies to the West of the island.

Chau seems to have been aware of the risks he was taking by visiting the tribe. He had made several attempts to reach the Sentinelese to preach Christianity — knowing it was illegal to go within five kilometres of the island.

He wrote to his family and told them not to blame the Sentinelese if he did not return safely. Indian police are trying to launch a murder investigation against the people who assisted Chau get to the prohibited island, and possibly against those on the island who killed him — if they can themselves set foot ashore safely.

But John and Lynda Chau, who lived in Washington State on the West Coast of the United States, do not seek retribution for the life of their son.

“He loved God, life, helping those in need, and had nothing but love for the Sentinelese people.”

“We forgive those reportedly responsible for his death. We also ask for the release of those friends he had in the Andaman Islands,” the family said in their Instagram statement.

BODY COULD BE LOST IN BATTLE TO PRESERVE TRIBE

The body of John Chau may never be recovered from the lost island where he fell in a volley of arrows fired by a reclusive tribe whose existence is threatened by the modern world, say experts.

The menace to the Sentinelese from Chau’s one-man invasion is such that tribal rights specialists say no murder charges will ever be laid and Chau’s body will have to stay hidden to protect what is probably the world’s last pre-neolithic tribe.

Indian authorities — who do not dare enforce their rule over North Sentinel island — have not even tried to send police ashore to question the tribe who have been greeting outsiders with hostility for centuries.

Police sent a boat near North Sentinel for the second time since the killing on Friday.

“Due precautions were taken by the team to ensure that this particularly vulnerable tribal group are not disturbed and distressed during this exercise,” said a police statement.

Fears that 21st century diseases as mild as the common cold could kill off the tribe, or that experiencing electricity and the internet would devastate their lifestyle, has left them in a guarded bubble that Chau sought to burst with his “Jesus loves you” message.

Pankaj Sekhsaria, a tribal rights expert and author on the Andaman and Nicobar Islands, said it would be “a futile exercise” to try to retrieve Chau’s body.

“I don’t think it is a good idea to go anywhere near (North Sentinel) because it will create conflict with the community there,” he told AFP.

“I don’t believe there is any safe way to retrieve the body without putting both the Sentinelese and those attempting it at risk,” added Sophie Grig, senior researcher for Survival International which campaigns for such isolated groups.

‘LET THEM BE THE WAY THEY ARE’

Anup Kapoor, an anthropology professor at the University of Delhi, said that anyone wanting to open a dialogue with the Sentinelese had to show they were “on the same level.”

“Don’t wear anything,” he recommended. “Only then you can hope to have some sort of interaction.”

Mr Kapoor once had contacts with the Onge, another Andamans tribe, adding: “It was only after I took off my clothes, except my underwear.” The lack of knowledge of the Sentinelese, believed to be the last surviving descendants of the first humans to arrive in Asia — and who 13th century adventurer Marco Polo called “brutish and savage” — is the main handicap.

“We have no clue about their communication systems, their history and culture, how can we go anywhere near them,” said Mr Kapoor.

“What we know is that they have been killed and persecuted historically by the British and the Japanese. They hate anyone in uniform. If they see someone in uniform, they will kill him on the spot.

“Let them be the way they are. Leave them in peace in the ecosystem they are in. Do not disturb them because that will only make them more aggressive,” says Mr Kapoor.

DOUBLE DILEMMA

Police in the Indian Ocean paradise are now wrestling with a double dilemma: how to answer the prayers of Chau’s family and maintain the privacy around North Sentinel that is essential for the tribe’s survival.

Andamans police chief Dependra Pathak has said no timeline can be given for finding a body.

And Sekhsaria warned Indian authorities may now have to strengthen surveillance around North Sentinel to prevent a Chau copycat.

“The administration is seized of the matter, they are already thinking about the surveillance,” he said without giving detail.

Indian outsiders have had a rough reception when going to North Sentinel. Arrows were fired at a helicopter that checked on the tribe after the devastating 2004 Indian Ocean tsunami. Two fishermen who strayed too close in 2006 were killed.

Police are talking with anthropologists and tribal welfare experts about the best way to establish contact.

The Anthropological Survey of India has had previous rudimentary contact.

“When we went there, nothing happened,” said the survey’s Andaman chief C. Raghu.

“Our seniors visited the island and they came back. It is because we are experts and know the pulse of the people.

“It’s not just the risk of disease. You also have to think of how to handle yourself, what to say and what to share with them. To them, whoever gets there is from the outside, new world.”