Rajiv Ratna Gandhi (20 August 1944 - 21 May 1991) was the 7th Prime Minister of the Republic of India, serving from his mother's death on 31 October 1984 until his resignation on 2 December 1989 following a general election defeat. He became the youngest Prime Minister of India when he took office at the age of 40. He was the elder son of Indira Gandhi and Feroze Gandhi. In 1991 while campaigning, he was assassinated by the Liberation Tigers of Tamil Eelam (LTTE or Tamil Tigers) group. His widow Sonia Gandhi became the leader of the Congress party in 1998, and led the party to victory in the 2004 elections.