Why were people protesting in Amritsar? Why were there troops in Amritsar?

Please answer this question the best you can and please answer it in your own words :)

the jallianwala bagh massacre also known as the amritsar massacre,took place on April 13 1919, when acting brigadier general Reginald Dyer ordered troops of the British indian army to fire their rifles into a crowd of unarmed indian civilians in jallianwala bagh, amritsar, Punjab killing at least 400 people

churchill warned that the soviet union had cut eastern europe off from the west with an "iron curtain."

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