The nation today paid homage to former prime minister Rajiv Gandhi on his 20th death anniversary. President Pratibha Patil, Prime Minister Manmohan Singh and Congress chief Sonia Gandhi were among the first to pay floral tribute to the late leader at 'Veer Bhumi', the memorial of Rajiv Gandhi. Rahul Gandhi and Priyanka Vadra also paid floral tributes to their father who was assassinated on May 21, 1991 at Sriperumbudur in Tamil Nadu during a poll campaign. Vice President Hamid Ansari, Home Minister P Chidambaram, Delhi Chief Minister Sheila Dikshit also paid homage to Gandhi. School children waving national flags were present at the memorial.In Puducherry, floral tribute was paid to former Prime Minister Rajiv Gandhi on his 20th death anniversary today. The Chief Minister Mr. N Rangasamy garlanded the Rajiv Gandhi statue at Rajiv Gandhi square. The Union Minister Mr. V Narayanasamy, former Chief Minister Mr. V.Vaithilingam, PCC President Mr.A.V. Subramanian and a large number of Congress and N.R Congress party functioneries also garlanded the statue. The Chief Minister Mr. N Rangasamy administered the anti-terrorism pledge to the participants. All religion prayer was also held.May 21 is also observed as Anti-Terrorism Day with an objective to keep youth away from terror activities. Among other activities, the Anti-terrorism and anti-violence pledge were taken in all Government offices, public sector undertakings and other public institutions on the day. This year the oath was taken yesterday itself as Central Government offices are closed today. Several other functions including debates, discussions, seminars, and lectures on the dangers of terrorism and violence being organised in schools, colleges and universities to mark the day.In Kerala, anti-terrorism day has been observed under the guidance of Chief Minister Oommen Chandy at Thiruvananthapuram today. In a brief function held at the state secretariat, he administered anti-terrorism pledge to officials. Finance minister K.M. Mani, Chief Secretary Dr.P. Prabhakaran and a number of state government officials were present. Earlier in the morning, Congress leaders and workers joined the chief minister at the KPCC headquarters in remembering the services of former Prime Minister Rajiv Gandhi to the nation and took anti-terrorism pledge.