Angry and upset that a motorist had sounded his horn at him earlier in a road incident, a human resource executive scratched his car after he spotted it parked in a shopping mall's carpark.

Jonathan Damian Poh Eng Wan, 55, was fined $4,800 yesterday for mischief. He had made full restitution of $820 to Mr Leong Liang Hee for the damage caused to his black Honda Odyssey car.

Investigations showed that Mr Leong was driving his Honda car along the middle lane of Moulmein Road on the day of the incident, with Poh's black Peugeot just ahead of him in the same lane.

After passing the junction of Moulmein Road and Jalan Tan Tock Seng, Mr Leong changed lanes, moving his vehicle into the adjacent lane on his right.

Poh simultaneously also tried to change lanes and cut in front of his car. This nearly caused a collision.

When Poh's car encroached into the lane, Mr Leong sounded the horn at Poh a few times, before slowing down and allowing Poh's car to move ahead of him and into the same lane.

Mr Leong later parked his car in Square 2 at Novena MRT station to run some errands.

After dropping off his wife at Tan Tock Seng Hospital at about 10.30am, Poh drove to Square 2, where he spotted Mr Leong's multi-purpose vehicle on level 6 of the carpark.

Feeling angry and upset that the driver had sounded the horn at him earlier, he decided to scratch the car in revenge.

He loitered for a while before walking to the rear of the Honda, squatted and scored the rear bumper, resulting in a long white scratch.

When Mr Leong returned to his car, he found the scratch on the rear bumper and reported the matter to the police the next day.

Poh was caught in the act by the Honda's in-car camera, and he was arrested the next day.

Pleading for leniency, Poh's lawyer T.M. Sinnadurai said his client's offence was "absolutely out of character", as attested by the testimonials submitted in the mitigation plea.

He said that Poh, who had served in the Republic of Singapore Air Force for 14 years, had compensated the victim long before he was charged, and had also apologised to Mr Leong.

District Judge Soh Tze Bian told Poh: "You are 55, shouldn't behave like a young man... very rash. Take this as a lesson and not commit any more crimes."

Poh could have been jailed for up to two years and/or fined for mischief by causing loss or damage to the amount of $500 or more.