In the case of the North Sentinelese, this incident in 1880 might have something to do with their hostility to the outside world.

> After several days, six Sentinelese—an elderly couple and four children—were taken to Port Blair. The colonial officer in charge of the operation wrote that the entire group "sickened rapidly, and the old man and his wife died, so the four children were sent back to their home with quantities of presents".

After the 2004 tsunami, indian government sent helicopters to see if they had survived and they started firing arrows at the helicopter. It's possible that they think the foreigners caused the tsunami.