The 94-year-old singer was taken to the hospital on Saturday after his health deteriorated.
"No change at all (in his condition). He is stable," a senior doctor at Narayana Hrudayalaya, told PTI.
Born in Kolkata, the Dadasaheb Phalke awardee currently resides in Bangalore after spending more than fifty years in Mumbai.
Having recorded more than 3,500 songs in a number of languages including Hindi and Bengali, he regaled generations of listeners with his romantic ballads, intricate raga-based songs, Qawwalis and fast-paced modern numbers, lending his voice to a number of Hindi and Bengali film stars.
His popular tracks include 'Poocho Na Kaise Maine' (Meri Surat Teri Aankhen), 'Ae Meri Zohra Jabeen' (Waqt), 'Zindagi Kaisi Hai Paheli' (Anand), 'Yeh Dosti' (Sholay) and 'Ek Chatur Naar' (Padosan).
Dey was being treated at his home for the past couple of weeks.
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