A senior Congress party politician has been jailed for life in what is being seen as the most important conviction so far over the 1984 anti-Sikh riots.
Sajjan Kumar, who was an MP at the time, was found guilty of inciting crowds to kill Sikhs.
In a scathing verdict, the Delhi high court judges said the accused evaded justice due to “political patronage”.
More than 3,000 Sikhs died in riots following the assassination of then PM Indira Gandhi by her Sikh bodyguards.
They were angry at her decision to send the army into the Golden Temple – Sikhism’s holiest shrine – to flush out militants earlier in the year.
The killing of Mrs Gandhi, who belonged to the Congress – now India’s main opposition party- saw mobs attack and murder members of the Sikh community across the country.
For 34 years, high-profile politicians accused of involvement in the anti-Sikh riots had evaded justice – on Monday this changed with Sajjan Kumar’s conviction.
Kumar, 73, had been previously acquitted by a lower court, but this verdict was challenged by the country’s top investigative agency which said he had been involved in a conspiracy of “terrifying proportions” with the police during the riots.
Nirpreet Kaur, whose father was burnt alive by mobs before her eyes, wept as she thanked the court for delivering justice after 34 years.
“I thank the judge and the whole prosecution team who brought the case to its logical conclusion. Had this conviction come earlier, I would have not suffered so much trauma,” Ms Kaur told BBC Punjabi’s Sarbjit Dhaliwal.
Ms Kaur said she was happy that Kumar had received a life sentence because a “death penalty would have meant he would have died in a moment, but now he will suffer”.
Kumar was convicted after several eyewitnesses testified against him for inciting mobs in Delhi’s Sultanpuri area.
One woman witness said she had seen him addressing a crowd, telling them that Sikhs had killed “his mother” – a reference to Mrs Gandhi.
Delhi high court Judges S Muralidhar and Vinod Goel found Kumar guilty of “criminal conspiracy, promoting enmity and acts against communal harmony” and ordered him not to leave the city and surrender by 31 December.
“In the summer of 1947, many people were massacred during the Partition of India. Thirty seven years later, Delhi witnessed a similar tragedy… The accused enjoyed political patronage and escaped trial,” the judges said.
Following the verdict, Sajjan Kumar, Delhi high court and #1984SikhGenocide were trending on Twitter in India with thousands of people tweeting about the case.