Shehnai maestro Ustad Bismillah Khan passed away after heart attack in Varanasi early morning on Monday. He was 90.
Khan was admitted to the Heritage Hospital on August 17 for treatment of electrolyte imbalance, family sources said.
The hospital authorities had even talked off discharging him in three to four days as he was improving day by day. However, his health deteriorated after midnight and he died around 2.30 am, they added.
The body has been taken to his residence at Harh Sarai in the city. The funeral is likely to take place in the evening.
Some top political leaders are expected to attend the last rites.
Born on March 21, 1916, Khan was awarded the Bharat Ratna in 2001.
He was also honoured with the Sangeet Natak Academi Award, the Tansen Award and the prestigious Padma Vibhushan.
The central government has declared one day's national mourning. In Uttar Pradesh, all government offices and schools were declared closed on Monday as a mark of respect to Khan who will be given a state funeral, the state government announced.