He tried to hit his victim's face with such force that when he missed and hit the ground instead, he fractured both hands.
Full-time national serviceman Shafiq Shah Husin Shah, 19, had joined a group of four in attacking his platoon mate at White Sands shopping centre in Pasir Ris last September.
They chased and hit their victim's head repeatedly while he was pinned down.
In court yesterday, Shafiq pleaded guilty to voluntarily causing hurt and two additional charges of motorcycle theft and riding it while under disqualification.
Two other charges of theft and driving without insurance were taken into consideration.
Shafiq was jailed for a year and disqualified from driving for two years.
Deputy Public Prosecutor Yvonne Poon, in asking for jail time for Shafiq, said: "His attacks were highly opportunistic in nature. The force used was so great that when two of his punches missed and hit the ground, he fractured his hands, as (Shafiq) claimed."
The victim, Mr Muhammed Haziq Ali, 22, who was in Shafiq's platoon, had allegedly bullied Mr Syed Omar Syed Salim, 20, who was also in the same platoon. They were all undergoing their Basic Military Training then.
Mr Omar decided to confront Mr Haziq and called Shafiq, his two older brothers and a friend along.
The five gathered at the outdoor seating area of McDonald's at White Sands on the afternoon of Sept 29.
When they saw Mr Haziq seated with other platoon mates inside the restaurant about an hour later, a member of the group grabbed him by the uniform and began shouting.
Mr Haziq managed to break free from his attackers and ran out of the restaurant, with the others chasing. Shafiq caught up with his victim and tripped him with his right leg.
He pinned him down by sitting on his chest before throwing eight punches at his victim's face. Two punches missed their marks and hit the ground.
The others in the group caught up and three of them were seen slapping, kicking and punching Mr Haziq's head. One of them even used a motorcycle helmet to hit the victim's head.
Two platoon mates, who saw the attack, tried to intervene. But they, too, were attacked.
The group involved in the assault left after one of Mr Omar's brothers told their victim to not bully Mr Omar any more.
Mr Haziq did not seek medical attention after the assault. The New Paper understands that his injuries were light.
Shafiq also pleaded guilty to stealing a motorcycle from a carpark at Yishun Avenue 5 last December. He had missed the last bus home and had no money for a taxi.
He had found a Yamaha key and tried his luck with motorcycles of the same marque at a open space carpark nearby. He found the motorcycle, a blue Yamaha RXZ, and rode it home.
Shafiq continued to use the bike for the next five days until he was arrested.
He had been convicted in 2011 and 2012 for vehicle theft and had been disqualified from holding a driving licence when he stole again last year.
Shafiq's lawyer, Mr Amarick Gill, of Trident Law Corporation, said in mitigation that Mr Haziq had hurled vulgarities at his client and insulted his parents.
Regarding the motorcycle theft, Mr Gill said his client was "extremely silly" and "all he had to do was to flag a cab".
Said Shafiq: "I am sorry for my actions. My (national service) training has opened up my mind and I have learnt to choose my friends wisely and control my temper."
For vehicle theft, he could have been jailed a maximum of seven years and fined. For causing hurt, he could have been jailed for two years and fined up to $5,000.
This article was published on May 20 in The New Paper.
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