SINGAPORE - Incensed by an acquaintance's taunts, former gang member Thennarasu Karupiah, 50, rained blows on the man's body and head even as onlookers tried to stop him.

When the man fell to the ground and gestured for him to stop, Thennarasu grabbed a metal chair and hit him repeatedly with it. He even stomped forcefully on the man's face thrice, after the victim had slumped to the floor again.

His assault in July 2016 proved fatal and the man died from traumatic head injury after being sent to the hospital.

On Monday (Oct 1), Thennarasu was sentenced to 15 years and five months in jail after he pleaded guilty at the High Court to culpable homicide not amounting to murder.

The court heard that Thennarasu and the victim, Arokiasamy Paul Rajoo, then 55, had known each other since the 1980s as they were both members of secret society gangs.

Both were at the Taj Mahal Bollywood Music Lounge in the early morning of July 13, 2016 and when Thennarasu went to the club's balcony to smoke, Arokiasamy followed him there, said Deputy Public Prosecutor (DPP) Dwayne Lum.

Arokiasamy asked Thennarasu why their old gang had not helped him when he was robbed the previous week. Thennarasu claimed he did not know about the robbery and the two men argued, said DPP Lum.

Arokiasamy then questioned Thennarasu's parentage and said something to the effect of"your mother did not give birth to you by one father". Thennarasu then threw the first punch at Arokiasamy's face.

The two managed to push past Thennarasu's friends to fight, with Thennarasu gaining the upper hand. At one point, he also picked up a metal chair to bash Arokiasamy repeatedly on his head and his body, said DPP Lum.

Thennarasu also stomped on Arokiasamy's face thrice before leaving the place, said DPP Lum.

Arokiasamy was later sent to the Singapore General Hospital, where he was operated on to remove the blood clots in his skull that had accumulated because of the assault. He was also found to have skull fractures and bruising of the brain.

Arokiasamy succumbed to his injuries and died on July 16, 2016.

In mitigation, Thennarasu's defence counsel Thangavelu called for Thennarasu to be given eight to 10 years' jail.

"He did not spoil for a fight, there was no animosity, no reason for him to assault... except for that split second... when the victim uttered vulgarities and insulted his mother," said Mr Thangavelu.

However, Justice Hoo Sheau Peng deemed the acts violent and brutal, and said there were plenty of opportunities for Thennarasu to disengage.

For culpable homicide, Thennarasu could have been jailed up to 20 years and fined or caned.