An American tourist was killed by arrows shot by members of the Sentinelese tribe, according to Indian police.

The tribe lives an isolated existence on North Sentinel Island. It has almost no contact with the interconnected world, speaks its own language, and lives without modern technology.

It's also off limits for visitors. Dependra Pathak, the director general of police in Andaman and Nicobar, said tourist and missionary John Allen Chau was illegally carried to North Sentinel Island by seven fishermen – each of whom has been arrested by Indian police.

Chau was a Christian missionary and had previously visited the the Andaman and Nicobar Islands in 2015 and 2016, according to CBS News. It's not clear if his attempts to reach the Sentinelese tribe were part of a religious mission.

But just because the tribe resists contact from outsiders doesn't mean we don't know anything about them. Here's what we know about the Sentinelese.

There are only a handful of them left

The Indian government doesn't include the Sentinelese in its census – in fact, it doesn't venture on to the island at all. It's counted its residents on the census based on photos taken from afar.

In its first census on the island, taken in 1991, it estimated 117 people were living there.

In 2011, it counted 15 people total.

They're hunter-gatherers and have their own language

Surveys of North Sentinel Island haven't found any evidence of agriculture. Instead, the community seems to be hunter-gatherers, getting food through fishing, hunting, and collecting wild plants living on the island.

The tribe also seems to have its own language. Attempts to contact them with Jarawa, the language of nearby islands, have been unsuccessful, according to Indian census documents.

North Sentinel Island is part of the Andaman Islands, home to many indigenous groups

The Andaman Islands are far from the coast of India and are home to the Andamanese, a group of various indigenous tribes that have historically been hunter-gatherers.

island tribes kill missionary bi 1The archipelago is located between India and Myanmar. (Google Maps)

island tribes kill missionary bi 2It's even isolated from the other islands in the archipelago. (Google Maps)

At this point in history, most of the groups that make up the Andamanese aren't as isolated from the rest of the world as the Sentinelese, which has maintained a reputation for keeping other groups away.

Since its language appears to be incompatible with that of other Andamanese groups, it's isolated from them as well.

The Sentinelese do not practice cannibalism

Since colonial times, there's been a pervasive rumour that the Sentinelese are cannibals. There's no evidence to support this, and a 2006 analysis from the Indian government following the death of two fishermen on the island concluded that the group does not practice cannibalism.

"The Sentinelese not eating the deceased is a contradiction to the common belief that these tribes are cannibals," the report said.

island tribes kill missionary bi 3A 2006 photo of the Sentinelese taking a boat stranded on the island. (Indian Coast Guard)

The false belief reportedly grew from misunderstanding the practice of a neighbouring tribe, the Onge, who cut up and burned the flesh of their deceased to prevent them from being consumed by evil spirits.

There have been a handful of recorded trips to the island

In the past couple of centuries, there have been a few recorded expeditions to North Sentinel Island.

In 1880, British colonizers kidnapped six Sentinelese people, two of whom died soon after, possibly because of contact with diseases they weren't immune to.

In the 1960s, Indian government researchers led several expeditions to the island. They laid the foundation for a 1974 National Geographic trip, during which island residents attacked the journalists.

From then on, trips to the island were mostly conducted for rescue missions. A ship crashed on the island in 1981, and the Indian government flew a helicopter over the island to survey the damage after the 2004 tsunami.

In 2006, India's coast guard attempted to recover the bodies of two fishermen who had been killed on the island.

The Indian government has offered them legal protection since 1970

India proclaimed North Sentinel Island as part of the Republic of India in 1970. Since then, it has controlled access to the island and kept it under watch with its coast guard.

It even passed a law in 2017 that made it illegal to post photos or videos of the Sentinelese, as well as other Andamanese groups, on social media.

But the current government removed some of the protections in August

India's current government, led by Prime Minister Narendra Modi, revoked some rules that protected the island. In August, it removed requirements to obtain a Restricted Area Permit for 29 islands in Andaman Islands, including North Sentinel Island.

That means that it's now legal for tourists to visit the islands, according to India Today, even though the Sentinelese have killed people and indigenous rights groups have called for their protection.

This article was originally published by Business Insider.

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