Watch video: Fans claim KK was 'sweating badly', complained about AC not working during last performance before death

Bollywood playback singer KK passed away on Tuesday night leaving the entire nation shocked and numb.

He had performed at a concert organised by Gurudas College at Nazrul Mancha in south Kolkata for almost an hour on Tuesday evening.

However, he complained of "feeling heavy" after reaching his hotel, and soon collapsed.

He was taken to a nearby private hospital around 10 pm where doctors declared him brought dead.

Now, a video of the late singer is going viral on the internet, which captures his last moments on stage. In the video, KK can be seen wiping off his face with a towel and speaking to a person from the management behind the stage.

Watch the video here:

The crowd can be heard cheering for him while his band performed in the auditorium.

Sharing the video, a Twitter user wrote that the auditorium was 'overcrowded' and that the air conditioner was not working properly.

"AC wasn't working at Nazrul Mancha. he performed their and complained abt it bcoz he was sweating so badly..it wasnt an open auditorium. watch it closely u can see the way he was sweating, closed auditorium, over crowded, Legend had to go due to authority's negligence," the tweet read.

According to reports, doctors are suspecting a cardiac arrest to be the cause of the singer's untimely demise, however, a complete post mortem will be conducted by the police.

KK is survived by his wife and two children who reached Kolkata on Wednesday morning.

A case of accidental death has been registered by the Kolkata Police and further investigation is underway.