Shanmugham (86), who fell down around 7:30 am was first rushed to a government hospital here. While preparations were on to shift him to Puducherry for further treatment, he died at 11:30 am, sources said.
A two-time Chief Minister, Shanmugham's political career spanned over five decades from 1954.
A bachelor, Shanmugham was Puducherry Congress president for nearly two and a half decades since 1978. He represented Puducherry in the Lok Sabha for three consecutive terms from 1980.
Elected from Yanam, he was Chief Minister from 2000 to 2001. He also successively became the Chief Minister without contesting the polls in 2001 for a short span of six months giving way to N Rangasamy, the present chief minister.
Shanmugham was the Leader of the Opposition between 1969 and 1973 when DMK formed the government and was a permanent special invitee to the AICC working committee from 1969 to 2001. He moved away from active politics in 2008 on health grounds.
Minister of State in the PMO, V Narayanasamy, who was groomed in politics by Shanmugham, said his death was a great loss to the party.
