A landscape technician has admitted sticking toothpicks in bus seats on four separate occasions on SBS Transit service 123M between July and August this year.
Although he said it was a prank and he did it because he was bored, the act damaged the seats and risked injuring other passengers, a court heard.
Lim Lye Seng, 60, pleaded guilty yesterday to two charges of mischief.
Two other counts of mischief will be considered in sentencing.
On Aug 4, Lim had his breakfast at a coffee shop near Tiong Bahru MRT station and took three toothpicks from the eatery.
After boarding the bus, he took the toothpicks out at around 6.20am and used them to perforate the seat next to him - causing $325.91 in damage.
Lim later alighted without removing the toothpicks.
The driver completed the trip at around 6.40am and parked the bus at HarbourFront Bus Interchange.
He spotted the toothpicks while conducting a check and informed an SBS Transit operations officer, who then alerted the police.
Lim admitted during the police investigation that he had committed the offence on three other occasions in July.
He admitted always using three toothpicks.
Deputy Public Prosecutor Rimplejit Kaur told District Judge Lim Keng Yeow that Lim has not made any restitution.
She added: "He further admitted that he was aware that his actions could have caused hurt to passengers on board SBS bus 123M."
Lim, who does not have a lawyer, pleaded for leniency. He told Judge Lim that he has two children and elderly parents to support.
The case has been adjourned to Nov 6.
For each count of mischief, Lim can be jailed for up to a year and also fined.