SINGAPORE — A punch that put a security guard in a monthlong coma, and later led to his death, has landed its thrower in jail.

The assailant, Teo Chin Lai, was sentenced to three years’ jail on Wednesday (Aug 24), after a four-day trial at a district court, where Teo denied his actions.

The incident took place at around 11.30pm on Nov 18, 2014, after Teo was reprimanded for urinating in public in Fajar Shopping Centre. He yanked the security guard out of the mall and threw a punch towards his upper body, the court heard.

The force of the blow fractured and dislocated the neck of the security guard, 74-year-old Chew Choo Chian. Mr Chew was left in a coma for a month, and later died of the injuries.

Deputy Public Prosecution Tan Si En said that it was an unprovoked attack, and that the victim had merely been carrying out his duties.

“(Teo) had assaulted an innocent security guard in the course of his duty,” she said. “There is a pressing need for general deterrence and protection of other persons in such positions, especially at night, when they would be more vulnerable to assault by drunken patrons.”

Experts had testified in court that the victim’s injuries were consistent with those seen on victims when cars flip over in traffic accidents or when they fall down stairs.

Appearing unrepresented in court, Teo, a chef at an economic rice stall, admitted that he had had “too many drinks” on the night of the incident.

“I wasn’t aware that he was working there. I saw the uncle fall and I wanted to save him. I would like to apologise to the uncle now,” said Teo, 53.

He pleaded for a fine instead of a jail term.

For causing grievous hurt, Teo could have been jailed up to 10 years, and fined or caned. No caning was imposed in this case, due to his age.

Speaking to reporters after the hearing, Mr Chew’s family said that he had been working at Fajar Shopping Centre for only 10 days when the assault happened. Prior to that, he had been working as a security guard elsewhere.

“He was just doing his job because someone complained about (Teo) urinating.... (Teo) never apologised during the trial. Today was the first time we heard an apology,” said his sister, known only as Madam Chew.

Mr Chew leaves behind a wife and two children. None of them attended the hearing.