A guest percussionist with a local band suddenly collapsed while performing on stage at the Esplanade's Outdoor Theatre on Friday night.
Mr Dalipkumar Hari, 60, who was better known as Charles Dalip or Charlie, suffered a sudden cardiac arrest at about 8.30pm.
He died on the way to the hospital.
He was performing with 60s Singapore band, The Esquires.
A member of The Esquires, Mr Farid Long, 49, who was on stage with him, said he was very shocked.
The guitarist told The New Paper that they were in the middle of playing the song Vehicle by US group Ides of March when Mr Dalipkumar suddenly collapsed.
"We were having a good time. He was in good form and doing the chorus and singing along. Everyone was standing. It was a high-volume, high-tempo show. We were laughing and joking. I turned to the audience and when I turned back, he was already falling down."
The band had played nine songs in the free concert by then.
Its saxophonist, Mr E. Gana, 64, said everyone stopped playing immediately.
He said: "The crew from Esplanade rushed out on stage and did CPR (cardio pulmonary resuscitation) on him on the stage itself. They were very fast."
A Singapore Civil Defence Force (SCDF) spokesman said they were alerted to a fainting case at 8.33pm and sent two ambulances and a fire bike to the Esplanade.
One of the ambulances took Mr Dalipkumar to Singapore General Hospital.
Mr Gana said that Mr Dalipkumar's son was among the audience during the performance.
"His son rushed up on stage and followed him in the ambulance. He later called me to tell me (about his father's death)."
The musician said he did not suspect anything wrong with Mr Dalipkumar, whom he believed did not have any heart problems.
"There were no signs at all. We had a sound test earlier in the day and then we went to makan (eat in Malay)." Esplanade spokesman Geraldine Kan said: "We extend our thoughts and prayers to his family."
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