I really don't understand what is going on here because of a lack of understanding of Urdu. So a constable is getting beat up? What made the crowd irate?
That little girl and his brother were going on a road and a Truck driver was driving violently and he was about to hit them both. That guy and his seven years old sister complained the Police Constable about that Truck driver, instead of doing something to the Truck driver the constable started slapping him and his seven years old sister. Public after seeing this started beating that constable.