Chennai: Tamil Nadu Chief Minister Jayalalithaa Jayaram died after a prolonged illness on Monday night.

“It is with indescribable grief, we announce the sad demise of our esteemed honourable chief minister of Tamil Nadu ... at 11:30pm (local time) today (Dec 5),” Chennai’s Apollo Hospital said in a statement.

Hundreds of devotees kept a round-the-clock vigil outside the private hospital in the state capital Chennai since she was first admitted in September suffering from a fever. Their numbers swelled since her condition worsened on Sunday.

Prime Minister Narendra Modi offered his condolences over her demise.

Her political party, AIADMK, said on Twitter: “Our beloved leader, the iron lady of India...Amma, is no more.”

To millions of her followers, the chief minister was known simply as Amma (mother).

The southern state had been tense since Sunday after reports that her health had worsened and she had been put on life support.

Jayalalithaa had earned the loyalty of many voters in the state with a series of highly populist schemes, including “Amma canteens” that provided lunch for just three rupees.

She was also one of the country’s most polarising politicians, accused of being dictatorial and was even jailed for corruption.