North Sentinel Island is one of the Andaman Islands in the Bay of Bengal and most of it is forested. It is a small island surrounded by coral reefs. People living in this area are known as Sentinelese. Their population is estimated to be between 50 and 400 individuals. They reject any contact with other people and if anybody tries to contact them, they are ready with their weapons. The Sentinelese are very protective of their own territory. But due to their hostile nature towards strangers, they have been saved from extinction for centuries. They are hunters and they also collect wild plants and go for fishing. They also happen to make tools and weapons from metal, which they recover from ships wrecked on the island’s reefs. There is no evidence of agricultural practice, however.
During 2004, the catastrophic tsunami had occurred and the Andaman Islands were being slashed by the terrific waves. So, the existence of the Sentinelese remained unknown. They were living just in the path of the waves and it was predicted that they could not have possibly survived it. But it was discovered that they had shifted someplace else before the tsunami came. This discovery was made when a helicopter flew low over the island and a Sentinelese man aimed his weapon and did not allow it to land.
They are thought to be directly descended from the first human populations to emerge from Africa and have probably lived in the Andaman Islands for up to 55,000 years. Due to their language, it is predicted that they haven't been in contact with other people for thousands of years. They are also known to be backward due to their habit of being isolated.
During 1990s, the Indian Government carried out a contact expedition. They sent boats where coconuts and gifts were being offered to the Sentinelese. In 1991, they began to accept the gifts directly. A few weeks later, a Pandit visited the islands and stayed there for a few days but towards the end of the visit, he was in the water with a group of Sentinelese when the dinghy drifted slightly away from him. And then one of the tribesmen pulled out a knife and pointed it threateningly at Pandit, obviously thinking that Pandit intended to stay on the island while his companions sailed off. The boat quickly returned, however, and Pandit left. After this incident, it was decided that the Sentinelese stay on their own and must be left alone.
Look at some pictures from the island.