Earlier today, President and Prime Minister also paid tributes on Twitter.
Amritsar: Congress President Rahul Gandhi on Saturday laid a wreath at the Jallianwala Bagh memorial on the completion of 100 years of the massacre.
The Congress president was accompanied by Punjab Chief Minister Captain Amarinder Singh and state minister Navjot Singh Sidhu, among others.
In the visitor's book, Rahul wrote that the cost of freedom must never be forgotten.
"The cost of freedom must never ever be forgotten. We salute the people of India who gave everything they had for it. Jai Hind," he wrote.
Earlier today, President Ram Nath Kovind and Prime Minister Narendra Modi also paid tributes on Twitter to those who lost their lives in the massacre.
The massacre took place on 13 April 1919 when troops of the British Indian Army under the command of Colonel Reginald Dyer fired machine guns into a crowd of unarmed protesters and pilgrims who had gathered in Jallianwala Bagh in Punjab's Amritsar on the occasion of Baisakhi.
The crowd had assembled peacefully at the venue to condemn the arrest of two national leaders -- Satya Pal and Saifuddin Kitchlew -- when they were fired at indiscriminately by General Dyer and his men.
According to British government records, 379 people including men, women, and children were killed while 1,200 were wounded in the firing. Other sources place the number of dead at well over 1,000.
Hundred years on, the United Kingdom is yet to give a full apology for the gruesome attack on unarmed protesters in Amritsar in 1919.
However, British Prime Minister Theresa May had recently said that the United Kingdom "deeply regrets" the 1919 massacre and called it a "shameful scar" on the British-Indian history.
"The tragedy of Jallianwalla Bagh in 1919 is a shameful scar on the British-Indian history. As her Majesty, the Queen said before visiting Jallianwala Bagh 1997, it is a distressing example of our past history with India. We deeply regret what happened and the suffering caused," May had said at the British Parliament earlier this week.