Story updated June 4, 2015
SINGAPORE - He braked on the expressway to make a rude hand gesture at a stranger - and caused a nine-vehicle pile-up that killed a motorcyclist.
Workshop manager Pang Chon Seng, 52, was sentenced to four months in prison for his dangerous driving on the Pan-Island Expressway (PIE) on June 19 last year.
Pang had been driving his Toyota Wish to work before 7am when he started swerving abruptly from lane to lane in order to harass motorcyclist Johann Johari Nazir.
The 31-year-old, who was riding with his wife on the pillion, felt Pang was driving dangerously close to him and stopped at the road shoulder near Toh Guan Road.
Pang then suddenly braked so that he could show Mr Johann both his middle fingers.
This forced the driver of a prime mover directly behind Pang to slam on the brakes.
At this time, lorry driver Lim Kok Aun, 48, was travelling behind the prime mover. He too braked hard, but his lorry veered to the right and spun into the path of motorcyclist Liow Yong Seng.
Mr Liow, 35, could not stop in time and crashed into the lorry with such force that his motorcycle broke into two pieces and flew across the PIE. He was found dead under the lorry.
Nine vehicles, not including Pang's car, Mr Johann's motorcycle and the prime mover, were involved in the accident, which unfolded as three separate chain collisions.
Meanwhile, Pang drove off.
Deputy Public Prosecutor Rachel Lee said that Pang had "deliberately chosen to persist in a continuous and prolonged dangerous manner of driving" which showed "a level of high disregard for other road users".
She highlighted the string of other traffic offences he had accumulated before this, including another charge of inconsiderate driving a little over six months before the incident.
Lim, the lorry driver, was fined $7,000 for his part in Mr Liow's death.
The prosecution argued that he had failed to keep a safe distance from the prime mover or kept a lookout for others on the road, and that this had contributed to the accident.
Both Pang and Lim were also disqualified from driving for four years from Wednesday.
For his reckless driving, Pang could have been jailed up to 12 months, fined up to $3,000 or both. Lim's negligence could have landed him in jail for up to two years, be given a fine, or both.
Additional reporting by Miranda Yeo
An earlier version of this story said that Lim Kok Aun was jailed for four weeks and fined $7,000. We are sorry for the error.