The health of Lakshmi Sehgal, a close associate of Netaji Subhash Chandra Bose, deteriorated on Saturday, doctors in Kanpur said.
"We have put her on ventilator support to boost her blood pressure," said Santosh Kumar, a doctor attending to the 97-year-old who was the first captain of the women's wing of Azad Hind Fauj or Indian National Army.
Cardiologists at the Kanpur Medical Centre, where Sehgal was admitted after suffering a heart attack on Thursday, said that her blood pressure dropped alarmingly low late on Friday.
Doctors admitted that things were not looking good for Sehgal who was the Left candidate in the 2002 presidential election.
She lost to A.P.J. Abdul Kalam.
"She is unconscious. We are monitoring her parameters and waiting for her to respond to the medication," a doctor told IANS.
Lakshmi Sehgal's daughter and senior CPI(M) leader Subhashini Ali was by her bedside.
Film director Shaad Ali, her grandson, was also in Kanpur.