It could be a case similar to Simi Grewal mistaking the flags of Islamic party fluttering in Mumbai Slums as Pakistani flag and making a fool of herself in a TV discussion post 26/11. Anyway if such a procession had really taken place there is nothing to be surprised, angered or have any reaction to it. It is possible for such things to happen in India. But then it should be a matter for discussion if someone dared to March in Pakistan with Indian flag on Independence day.
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It is 100000% true, because of the mistake made by nehru and gandhiji we are facing this type of dangerous situation, even now if we unitedly take this menace on head on we can still save our bharath(mata) and ourselves