When Colonel Dyer got to know about the gathering, he reached the venue with around 50 soldiers and asked them to fire on those people.
The firing went on for about 10 minutes and around 1,650 rounds of bullets were fired.
According to British government records, 379 people including men, women, and children were killed while 1,200 were injured in the indiscriminate firing ordered by Colonel Reginald Dyer.
Udham Singh, who was a member of the revolutionist Ghadar party, shot Colonel Reginald Dyer on March 13, 1940 to avenge the massacre.
Prime Minister Narendra Modi paid tributes to the victims and said that their unparalleled courage and sacrifice will keep motivating the coming generations.