Sikhs were only being killed. Not Hindus, which defines a RIOT.
Secondly, normal Hindus weren't involved. They were busy saving their neighbours. It was hired goons from UP and Bihar who were running loose while the Police stood and watched on the government's orders, while the army wasn't allowed to enter Delhi.
Bindharawala was a monster, created by Indira Gandhi, who turned rogue similar to Osama who was created by the US.
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