Popular bollywood singer Krishnakumar Kunnath also known as KK, who was in Kolkata for a concert, passed away on Tuesday evening at the age of 53. The playback singer reportedly collapsed after the concert and was rushed to a private hospital on Diamond Harbor Road after falling ill, where he was pronounced dead. He was performing at a concert at Nazrul Mancha for Gurudas college, in Ultodanga district.