Playback singer Krishnakumar Kunnath, better known as KK, died about an hour after he had finished a performance before a packed audience at south Calcutta’s Nazrul Mancha. He was 53.

KK had complained of feeling unwell on his return to Oberoi Grand hotel and he is believed to have passed away on his way to hospital.

He was declared brought dead at Calcutta Medical Research Institute in Alipore.

Television channel ABP Ananda reported that the singer was feeling uneasy even during the concert. He had apparently complained about the glare of the lights. On the way to hotel, he had said he was feeling cold.

“He told his secretary Hitesh Bhatt that he was feeling cold when the car’s air conditioner was switched on while returning to the hotel this evening. In the hotel, a few fans were waiting for him to take selfies. He politely refused and said he was not feeling well today,” show arranger Tochan Ghosh told this newspaper.

Ghosh said KK retired to his room and collapsed on a sofa. Bhatt, who was present in the room, rushed him to hospital.

A CMRI official said KK was brought to the hospital between 9.45pm and 10pm. “He was brought dead here. We have handed over the body to police. For tonight, the body will be kept at the hospital’s mortuary,” the official said.

KK had come to Calcutta on Sunday for two performances in the city — both at Nazrul Mancha. Monday’s event was organised by Thakurpukur’s Vivekananda College. Tuesday’s show was the annual social of Gurudas Mahavidyalaya in Ultadanga.

KK’s popularity spanned several generations. Over the years, KK, born in Delhi, came to be hailed as one of the more romantic male voices in films. He had sung in several languages.

Bengal power and youth affairs minister Aroop Biswas, who was at CMRI hospital, said: “I was returning from office when I received a phone call from Anupam Roy (singer) who asked me if the news was true. I said ‘let me check’…. He was brought dead at the hospital. I am speechless.”

In an interview with The Telegraph t2 in 2014, KK had said: “I love the way I have been, a little laidback, a little low profile.… My friends keep telling me, ‘You are hardly seen’. I used to believe that I am a singer and you will just have to hear my songs. Times are changing. I am not talking about insecurities. I am a loner. The only place where I can handle crowd is the stage.”

“You can have a great concert in Calcutta and sing your heart out. There is something about Nazrul Mancha. It is like the Super Bowl! Because it has that energy there,” KK had told t2.

Rohit Shaw, an engineering student who went to see Tuesday’s event, said the number of people who turned up at KK’s show appeared to be far more than the auditorium’s capacity. “There was a time when the organisers were forced to open the gates. The air-conditioners were not working. Many people started shouting and protesting. The police came,” Shaw said.

KK is survived by his wife and two children, said Ghosh. The family is expected to reach Calcutta on Wednesday morning.