'KK died of cardiac arrest, had prolonged heart issues'

Celebrated singer KK passed away on May 31 after a final performance in Kolkata. He had expressed uneasiness while at his hotel and was rushed to a hospital, but he could not be saved. According to the initial post-mortem report, KK suffered a massive cardiac arrest.

from Times of India https://timesofindia.indiatimes.com/entertainment/hindi/music/kks-post-mortem-report-suggests-singer-suffered-a-cardiac-arrest-had-chronic-liver-and-lung-issues-report/articleshow/91943501.cms