Veteran Environmental activist GD Agarwal died in a hospital here on Thursday, 111 days after he began a fast for a pollution-free Ganga. He was 86.
Agarwal, who began his fast on June 22 demanding government measures to save the Ganga, died of a heart attack at the All India Institute of Medical Sciences in Rishikesh, its director Ravi Kant said.
Agarwal was admitted to hospital on Wednesday after he even gave up drinking water.
Local authorities imposed section 144 of the CrPC, which bans assembly of people, around the venue of the protest and the activist was picked up and taken to the hospital.
Dr Ravi Kant said Agarwal suffered from hernia, high blood pressure and coronary artery disease and the fast worsened his condition.
G D Agarwal, also known as Swami Gyanswaroop Sanand in his later years, has been a professor at the Indian Institute of Technology in Kanpur and served on the Central Pollution Control Board.
He was protesting against hydroelectric projects on the Ganga's tributaries and had demanded a law to protect the river.
Earlier, he had rejected a plea from Haridwar MP Ramesh Pokhriyal Nishank to end the fast, following assurances on his demands from the Centre.
Agarwal had been campaigning for the Ganga for several years and undertook a similar fast earlier as well.
A few years ago, he adopted Swami Gyanswaroop Sanand as his name.
As his fast continued, on September 9 Agarwal announced he will give up water in October.
The National Mission for Clean Ganga officials then talked with him and Congress president Rahul Gandhi expressed support.
The Ganga activist had donated his organs for medical research at the Rishikesh AIIMS, its director said.
(With inputs from agencies.)