Complex sentence: The story begins with Sikhs and Hindus being attacked by Muslims in Pakistan when trying to migrate to India on a train in response to the killing of Muslims going to Pakistan from India to get revenge, Sikhs and Hindus react by doing the same thing.
Split into simpler sentences: The story begins with Sikhs and Hindus being attacked by Muslims in Pakistan when trying to migrate to India on a train in response to the killing of Muslims going to Pakistan from India. To get revenge, Sikhs and Hindus react by doing the same thing.