India observes the centenary of Jallianwala Bagh massacre today. It is considered as one of the worst atrocities of British colonial rule in India. More than 3,000 people including women and children were killed on this day. India will never be able to forget the terrible tragedy. British Prime Minister Theresa May described Jallianwala Bagh massacre as a 'shameful scar' on British Indian history, while the Opposition leader of UK demanded the government to express apology for the brutal act done by their ancestors.