From Wikipedia

Operation Blue Star

Operation Blue Star) 3– 6 June 1984 was an Indian military operation, ordered by Indira Gandhi, then Prime Minister of India, under the pretext of removing Sikh separatists from the Golden Temple in Amritsar. The activists, led by Sant Jarnail Singh Bhindranwale, were accused of amassing weapons in the Sikh temple.

The military assault led to an uproar amongst Sikhs worldwide and the increased tension following the action led to assaults on members of the Sikh community within India. Some Sikh soldiers in the Indian army mutinied, many Sikhs resigned from armed and civil administrative office and a few returned awards and honors they had received from the Indian government. Four months after the operation, on 31 October 1984, Indira Gandhi was assassinated by two of her Sikh bodyguards in what is viewed as an act of vengeance. Following her assassination, more than 5000 Sikhs were killed in anti-Sikh pogroms. Within the Sikh community itself, Operation Blue Star has taken on considerable historical significance and is often compared to what Sikhs call 'the great massacre', the 1761 slaughter of Sikhs by the Afghan invader Ahmad Shah Abdali.