Their lawyers argued that the trio had planned only to rob.

When their victim, Mr Thien Naing, 41, an air-con repairman, resisted and pulled out a penknife, Hamir Hasim, 23, Kamal Kupli, 24, and Abdul Malik Usman, 28, beat him up.

The brutal attack, which took place in a dimly-lit footpath near Block 19 Upper Boon Keng Road at about midnight on Christmas Eve in 2005, killed Mr Thien.

The robbers got away with only $40.

The Court of Appeal on Monday heard that Hasim, a gardener, had grabbed the penknife and stabbed Mr Thien, six times.

When the victim fell on the ground, Kamal and Abdul Malik, both cleaners, stomped on Mr Thien's head.

Defence counsel said that the three attackers could not have known the beating would kill Mr Thien.

To this, Justice of Appeal V.K. Rajah retorted: 'It doesn't take a rocket scientist to realise that stomping on a person's head would result in serious injuries that could prove fatal.'

The court, also comprising Justice of Appeal Andrew Phang and Justice Tan Lee Meng, also noted that the beating was sustained and wanton.

The stomping left Mr Thien's forehead flattened on one side with an imprint of a shoe pattern.

The autopsy revealed that he died of head injuries.

A fourth accomplice, Benedict Inyang Igai, 20, also a Malaysian, who acted as a lookout, has been dealt with for robbery.

In court was Hamir's father, taxi-driver Hasim Lasin, 50, who came down from Malacca, and two of Malik's brothers, who are working here.

All said that they were too sad to talk to the press.