Among the Andaman and Sentinel Islands lies an island simply dubbed "North Sentinel Island." It is mostly comprised of trees and bushes and what have you in a forest land, but there is also a very secretive and antisocial indigenous tribe. They're called the Sentinelese, and do not speak any known language but their own custom one. The tribe is extremely hostile and will attack anything and anyone that gets within its 3-mile exclusion range. If within the range, one will be attacked by javelins and arrows. Several have died because of them trespassing, the most recent being two fishermen who washed too close for comfort to the island on an illegal fishing trip.
Here is an image of the Sentinelese guarding their territory.
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