Anna Hazare was on Wednesday admitted to a local hospital for a medical check-up after he complained of fatigue and weakness.
Hazare, 74, had arrived in Nashik on Wednesday morning from Dhule town as part of his state-wide tour for a strong Lokayukta Bill.
He has been taken to the Saibaba Heart Institute and Research Centre, where he is being examined by doctors, hospital sources said.
"Hazare cancelled his Nandurbar district tour due to fatigue and weakness," said P B Karanjkar, president of the Nashik unit of the Bhratachar Virodhi Andolan.
He added that the Gandhian is scheduled to address a public meeting in Nashik on Thursday evening.
Hazare has been on a month-long tour of the state on the Lokayukta Bill issue from May 1.
In January, Hazare had been hospitalised for a week, which had forced him to call off his tour of the five assembly poll-bound states.
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