T. N. Pandit, is the world’s foremost expert on the Sentinelese. In fact, he literally wrote the book on them: The Sentinelese. He studied them for over 20 years! Pandit started making journeys to the island where the visiting party would leave ‘gifts’ of cloth and candy in empty huts. The Sentinelese themselves had disappeared into the forest.
Finally, one time, the tribespeople came out to the boat without their bows and arrows! Pandit got out and handed the tribesmen coconuts, but when he ran out, the tribespeople pulled out knives. It became quite clear that the coconuts were welcome but visitors were not. He quickly got back into the boat and they turned out to sea. As he left, a single arrow hit the boat. He took its meaning as: Don’t come back. He didn’t.
Pandit was asked to comment on the death of John Allen Chau. He was surprised that Chau was killed. He said the Sentinelese warn before they kill. When he learned that a single arrow was shot at a book Chau was carrying and the next day they destroyed his small boat, he said those were two clear warnings. The Sentinelese people should be left alone. They made that clear before Chau tried to impose himself on them.