In 2013, a 12-year-old boy riding across a zebra crossing in Choa Chu Kang on his bicycle was knocked down by an SMRT bus and dragged for about 10m.

His left foot, which was pinned under the bus, was seriously crushed in the accident. Doctors managed to save his foot after five operations, but he was left with permanent disabilities.

The boy's father, represented by Mr Tan Lian Beng, sued SMRT and the bus driver on his behalf, seeking damages of about $638,000.

The claims include compensation for pain and suffering, medical expenses and loss of future earnings, and diminished earning capacity.

Yesterday, a hearing in the High Court started to determine the issues of liability and quantum of damages.

Neither the boy, who is now in Secondary 4, nor his father, a senior executive in a construction company, can be named as he is a minor.

On Feb 22, 2013, the boy was cycling on the pavement on Choa Chu Kang North 5 on his way home, when he stopped briefly at a zebra crossing. He testified that he had assumed the approaching bus would stop for him, so he proceeded to cycle across the road.

But the bus did not stop. The boy, with his left foot and bicycle pinned under the bus, banged on the door to get the driver's attention. After the bus came to a stop, the driver pulled him out from under the bus.

The boy was hospitalised for a month and recuperated at home for about a week before he returned to school.

As a result of the accident, he cannot move his ankle and toes freely, suffers pain when walking or standing for some time, and is likely to develop arthritis in the next few years.

He used to play many sports, but is no longer able to take part in physical activities, he said.

The boy, who is in the technical stream and said he was "not very good" in his studies, said he would likely have to look for a blue-collar job requiring some form of physical abilities.

He said his ambition is to be a chef and wants to pursue culinary arts courses after secondary school. But as chefs have to stand for long hours, he is likely to have to take a pay cut, he argued.

The trial continues.

Separately, the bus driver, Mr Muruga Muniandy, was fined $1,200 and banned from driving for three months after he pleaded guilty to inconsiderate driving in November 2013.