Veteran DMK leader and longest serving General Secretary of the party K Anbazhagan died at a private hospital here late tonight after a prolonged illness.
He has been serving as the General Secretary for more than four decades.
Ninety-seven-year old Mr Anbazhagan, a very close associate and trusted aide of late DMK stalwarts C N Annadurai and M Karunanidhi, was admitted to Apollo Hospitals due to age related ailments on February 24 and was shifted to the ICU.
His condition turned critical and he was put on ventilator support for the last few days.
Mr Anbazhagan, who was elected to the State Assembly nine times and had served as the Finance Minister and Leader of the House during the DMK regime, breathed his last at around 0100 hrs.
His wife predeceased him in December 2012 at the age of 90.
Senior DMK leaders, including Party President M K Stalin, MPs, MLAs and former Ministers paid their last respects.
Condoling his death, Mr Stalin recalled his services to the public life and announced a seven-day mourning as a mark of respect to the departed leader.
In a statement here, he said all the party functions were cancelled and the party flag would fly at half mast during the week long mourning period.
Later, the body of the nonagenarian leader was taken to his residence at Kilpauk where it was kept for public homage.
Earlier, talking to reporters after visited him twice in the hospital to enquire about his health condition, Mr Stalin said despite the best of treatment being provided by the doctors, the veteran leader was not responding to it due to old age.
He had served as the General secretary of the DMK till his death ever since he was appointed to the post in 1977.
As the news spread, DMK cadres thronged the hospital, where police have strengthened security arrangements.
The senior leader has stopped attending public functions and has been taking rest at home for the last one year due to old age.
Mr Kalyanasundaram Anbazhagan, affectionately called as 'Perasiriyar' (Professor) by Mr Karunanidhi and DMK leaders, was elected as a member of the State Assembly on nine occasions and had also served as the Social Welfare Minister in 1971 before becoming Finance Minister.
He had also served a member of Lok Sabha between 1967 and 1971 and has been a member of the now defunct MLC from 1962 to 67, before becoming MLA for the first time from the city.
Born as Ramaiah at Kattoor near Tiruvarur in Thanjavur district (now Tiruvarur District) of Madras Presidency, British India on December 19, 1922, he changed his name to Anbazhagan due to his love for Tamil language.
He had earned finished his M.A (Tamil) degree from Annamalai University.
A fine orator and has good command over Tamil language, Anbazhagan was also a sound academician and a poet and has published works like 'Urimai vaazhvu', 'Viduthalaik kavignar', 'Pesum kalai valarpom', 'Thamizh kadal', 'Alai osai' and 'Thamizhar thirumanamum inamaanamum.'
He had given up his MLA post, representing Park Town constituency, in 1984 in support of Eelam Tamils during the ethnic crisis in Sri Lanka.