Well-known Bollywood singer Krishnakumar Kunnath, popularly known as KK, died in Kolkata on Tuesday night, officials said.
He was 53.
KK was feeling unwell after reaching his hotel, following a performance at a concert in the evening where he sang for almost an hour, officials said.
He was taken to a CMRI hospital in south Kolkata where doctors declared him brought dead, they said.
"It's unfortunate that we could not treat him," a senior official of the hospital said.
One of the most versatile singers of the Indian film industry, KK has recorded songs in several languages, including Hindi, Tamil, Telugu, Kannada, Malayalam, Marathi and Bengali.
He is survived by his wife and children.
KK is best known for his songs like Zindagi Do Pal Ki from the movie Kites, Aankhon Mein Teri from the movie Om Shanti Om, Khuda Jaane from the movie Bachna Ae Haseeno, and Tadap Tadap from the movie Hum Dil De Chuke Sanam.
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