The 86-year-old Congress leader had been admitted to the Medanta hospital in Gurgaon for a cardiac problem, officials from the hospital said.
He is survived by his wife, two sons and a daughter.
Ola was a member of the Rajasthan legislative assembly from 1957 to 1990, and a cabinet minister in the state government from 1980 to 1990.
He received the Padma Shri in 1968 for social work.
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