This is a well known event so Black Hole of Calcutta should suffice.
I did a unit of Indian history a long time ago. My textbook was similar to the wikipedia entry. But at the time I read somewhere else that historians have cast doubt on whether it happened, and if so to what extent; fewer prisoners may have died than in earlier accounts. Even the Wikipedia article above has been marked as needing more sources.
I am not Indian. I have no emotional investment in the answer. I just would like to know; I was a good little student at the time and put the skeptical textbook to one side.