Indian exploratory parties under orders to establish friendly relations with the Sentinelese made brief landings on the island every few years beginning in 1967.[1] In 1975, Leopold III of Belgium, on a tour of the Andamans, was brought by local dignitaries for an overnight cruise to the waters off North Sentinel Island.[5] The cargo ships MV Rusley and MV Primrose ran aground on coastal reefs in the summer of 1977 and August 1981 respectively. The Sentinelese are known to have scavenged these wrecks for iron. Settlers from Port Blair also visited the sites to recover cargo. In 1991, salvage operators were authorized to dismantle the ships.[8]
On 2 August 1981, the ship Primrose grounded on the North Sentinel Island reef. A few days later, crewmen on the immobile vessel observed that small black men were carrying spears and arrows and building boats on the beach. The captain of the Primrose radioed for an urgent drop of firearms so the crew could defend themselves, but did not receive them. Heavy seas kept the islanders away from the ship. After a week, the crew were rescued by a helicopter working under contract to the Indian Oil And Natural Gas Commission (ONGC).
The first peaceful contact with the Sentinelese was made by Trilokinath Pandit, a director of the Anthropological Survey of India, and his colleagues on 4 January 1991.[9][10] Indian visits to the island ceased in 1997.[1]
The Sentinelese apparently survived the 2004 Indian Ocean earthquake and its after-effects, including the tsunami and the uplifting of the island. Three days after the event, an Indian government helicopter observed several of them, who shot arrows and threw stones at the hovering aircraft with the apparent intent of repelling it.[1][6][11] Although the fishing grounds of the Sentinelese were disturbed, they appear to have adapted to the island's current conditions.[12]
On 26 January 2006, two fishermen were killed by Sentinelese when their boat drifted near the island.[13]