A stampede on Wednesday among thousands of mourners at the funeral of powerful southern Indian politician Muthuvel Karunanidhi killed two people and injured 47, a doctor at a government hospital said.

Karunanidhi, a dominant figure in the politics of southern India for half a century who had been chief minister of Tamil Nadu five times, died on Tuesday aged 94.

Television broadcast images of thousands gathered in the state capital, Chennai, to pay their last respects to the leader at a funeral attended by senior politicians, including Prime Minister Narendra Modi.

The stampede happened when a sudden rush among mourners arriving at the site caused many to lose their balance and fall, the Times of India newspaper said.

"A man and a woman were brought dead to the hospital," A. Elango, an official of the Rajiv Gandhi general hospital, told Reuters, adding that 47 people had been admitted for minor injuries.

Karunanidhi, who always appeared in public with dark glasses and a yellow shawl draped over his shoulder, built his political machine as a crusader for social justice.

He was known for drawing foreign investors to India's second largest state economy, overseeing its emergence as an industrial powerhouse and being credited with opening many industrial and technology parks.