A rare photo of two members of the Sentinelese tribe, which is protected under Indian law and whose population is estimated to be below 50. This photo was taken by the Indian Coast Guard

An American man was killed on an island inhabited by a tribe known to resist outside contact in the Andaman and Nicobar Islands. And, his body still lies there.

The American was identified as 27-year-old John Allen Chau, who sources said was a Christian missionary who wanted to convert the Sentinelese tribe that inhabits the island where he was killed.

Chau was killed by members of this tribe, which is protected under Indian law, a senior police officer told India Today TV.

The officer stressed that the Sentinelese must be left alone and that any forced contact with the outside world could put them in danger.

Chau was murdered on the North Sentinel Island, which is part of the Andaman Islands, and seven people have been arrested in connection with the murder.

The seven arrested are local fishermen who allegedly helped Chau reach the North Sentinel Island.

The Andaman and Nicobar Police has registered a case of murder. Another complaint has been filed in Chennai by the US consulate there. The Chennai FIR is a missing persons complaint that was filed at the behest of Chau's mother.

27-year-old John Allen Chau was a Christian missionary who wanted to convert the Sentinelese tribe

"We are aware of reports concerning a US citizen in the Andaman and Nicobar Islands. The welfare and safety of US citizens abroad is one of the highest priorities of the US Department of State," a US Consulate spokesperson said.

"When a US citizen is missing, we work closely with local authorities as they carry out their search efforts. Due to privacy considerations, we have no further comment," the spokesperson said.

ATTACKED BY ARROWS

Deepak Yadav, a Superintendent of Police in the Andaman and Nicobar Islands Criminal Investigation Department, told India Today TV that Chau reached the union territory on October 16.

Chau, sources said, was a missionary who wanted to meet the Sentinelese in order to convert them to Christianity. He was also looking for "adventure", the source said.

According to SP Deepak Yadav, Chau contacted some fishermen in order to reach the North Sentinel Island. A group of seven fishermen agreed to help and took to a forest located on the island.

The Sentinelese is a sensitive tribe living in that area for 60,000 years. They should not be contacted. They could be prone to diseases from outside world. The Coast Guard and Indian Navy carry out patrolling to prevent people from entering - Deepak Yadav, SP, CID

The fishermen stayed away, but Chau ventured deep into the jungle. This was on November 14.

The fishermen later saw Chau being attacked with arrows. "He was attacked by arrows but he continued walking," news agency AFP reported, quoting sources. Local fishermen also saw the Sentinelese tying Chu's body to a rope and dragged it along the ground.

The CID SP, Deepak Yadav, told India Today TV, "One of the fishermen saw Chau's body getting buried by the tribals. Chau was killed with an arrow."

Yadav said that authorities are still trying to recover Chau's body. "We did an aerial sortie yesterday to assess the situation," Yadav said.

The red pin shows where the North Sentinal Island is located

The most obvious huddle in recovering Chau's body is the Sentinelese fiercely oppose outside contact -- so much so that once when a helicopter hovered above them to check on their health, they shot arrows at it (more on that later).

Yadav also said that a "strong case" has been registered against the fishermen, "who should not have taken Chau there."

"It's very unfortunate. It's a sensitive tribe living in that area for 60,000 years. They should not be contacted," Yadav said. "They could be prone to diseases from outside world. The Coast Guard and Indian Navy carry out patrolling to prevent people from entering."

The North Sentinel Island, where Chau's body is still lying, is home to the Sentinelese, an indigenous tribe that furiously rejects outside contact.

The Indian law protects the Sentinelese people, whose number is estimated to be under 50. They famously do not use money.

They cannot be prosecuted and any contact with them or entry into areas inhabited by them is illegal.

Even taking videos of the Sentinelese people is prohibited. In 2017, the government had clarified that the Sentinelese are identified as an "aboriginal tribe" and that videos showing them cannot be uploaded on social media or the internet.

WHO ARE THE SENTINELESE?

The 2011 Census of India counted 15 Sentinelese people on the North Sentinel Island.

There are 12 men and three women. The numbers could be higher since the census was done from a distance.

According to Survival International, a global rights group that campaigns for tribal people, the Sentinelese "vigorously reject" contact with the outside world.

So much so that during the 2004 tsunami, the Sentinelese attempted to shoot arrows at helicopters of the Indian Coast Guard.

A member of the Sentinelese shoots an arrow at an Indian Coast Guard helicopter that flew over the North Sentinel Island in 2004 to assess the damage -- if any -- caused by the 2004 tsunami (Photo: Indian Coast Guard/Survival International)

The helicopters flew over the North Sentinel Island in order to assess the damage the Sentinelese may have suffered due to the tsunami. The extent of that damage -- if any -- still remains unknown.

According to the Survival International, the Sentinelese killed two Indian fishermen who inadvertently landed on the island.

The fishermen had moored their boat near the island and had slept off. But the boat's anchor rope broke and the boat drifted to the island's shores.

The rights group also says that the Sentinelese survive by hunting or gathering food. The Sentinelese are also known to have the ability to build boats and fish in shallow waters.

The Indian government has decided not to make any attempts to contact the Sentinelese (such attempts were made in the past).

Occasional reconnaissance missions from boats anchored more than an arrow's throw away are carried out to check whether all is well with the Sentinelese.

(With inputs Priyamvatha P in Chennai and Geeta Mohan in New Delhi)

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