Kumar, 90, was taken to the intensive care unit around 9 pm. His condition was said to be stable on Monday morning, hospital sources said. Doctors said the ageing actor suffered a massive heart attack on the interior wall. Surgery might not be a viable option at this stage, they said.
Born as Mohammad Yusuf Khan in Peshawar (now in Pakistan) in 1922, Kumar's acting career spanned over six decades. He was the first actor to receive Filmfare Best Actor honour and shares the highest number of the award in that category with Shah Rukh Khan (eight).
Doctors said surgery might not be a viable option for the 90-year-old actor
He was conferred the Padma Bhushan in 1991 and Dadasaheb Phalke Award in 1994 for his glorious contribution to the Indian cinema. In 1998, he was awarded Nishan-e-Imtiaz, the highest civilian award of Pakistan by that country's government.
Kumar, married to yesteryear's actress Saira Banu, also served as a member of the Rajya Sabha between 2000 and 2006.
Andaz, Aan, Devdas, Azaad, Mughal-e-Azam, Ganga Jamuna, Ram Aur Shyam and Saudagar are some of his notable films.