The Hyderabad Amok case is one of the earliest documented cases of a mass shooting in world history. In June 1878, a sepoy in the British Indian Army killed 6 people and injured 4 in Sindh. The unnamed Sepoy man from Baloch, killed his mistress whom he had suspected of infidelity. Armed with 100 rounds of ammunition, he went on a shooting spree in Hyderabad. He gunned down anyone who came his way and was eventually shot by an armed officer.
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Hyderabad amok case Wikipedia(Text) CC BY-SA