Where:

Sentinelese lives in the North Sentinel Island, a few miles west of Port Blair. They are known to aggressively protect their isolation from the rest of the world — many attempts to make contact with them in the 1970s and 1990s failed after they attacked using bow and arrow. In 2006, two fishermen were killed after they slept overnight in their boat near the

and approached its shore.

Before time:

The indigenous group has been living on the island for centuries and is thought to have even foiled attempts by Colonial British to make contact. 13th-century explorer Marco Polo described them as: "They are a most violent and cruel generation who seem to eat everybody they catch."

How many:

The 2011 Census of India says there are 10 households in the North Sentinel island, comprising 15 individuals (12 male and 3 female). But that is a

— no one knows for sure how many tribesmen live there, even the Indian government, replying to a

query in 2017, said the exact population of the island is unknown. There were concerns that the 2004 Tsunami could have wiped them off until a coast guard helicopter sent to investigate was attacked by bow-and-arrow-wielding tribesmen.

Legal protection:

It is illegal — under the Andaman and Nicobar Islands (Protection of Aboriginal Tribes) Regulation, 1956 — to make contact with the Sentinelese or even venture up to 5 kms from its shore, and for a good reason. Centuries of isolation from the rest of humanity means these islanders would not have gained the immunity to common diseases and microbes that we carry. Making contact with them, hence, could prove fatal to them. A study says of the 238 Amazonian indigenous tribes in Brazil that have been contacted in the last several decades, three quarters went extinct and those who survived saw their mortality rate shoot up by 80%.

Others in India

: Sentinelese is not the only tribes continuing to live their modest ways today. Jarawa and Onge and Great Andamanese are other indigenous tribes living in the island cluster. But unlike Sentinelese, these tribes have made contact with the rest of humanity — in fact, India has built a highway through the Jarawa forest, though Supreme Court in 2013 barred entry of tourist there.