A bus passenger who hit a bus captain's head three times was fined $4,000 on Friday.

Cleaner Chng Eng Khiang, 57, pleaded guilty to causing hurt to Mr Xu Tingqiang by a rash act which endangered the personal safety of others on the SBS Transit bus travelling along Boon Lay Avenue on Aug 9 this year.

The court heard that Chng was slow in alighting at the bus stop near River Valley High School along Boon Lay Avenue that evening. He only managed to stand up after Mr Xu, a 34-year-old Chinese national, had started driving out of the bus stop lane.

He pressed the bell three times but the victim did not stop. Chng then walked up to Mr Xu and started scolding him. An argument ensued and Chng hit the victim's head three times while the latter was still driving the double-decker bus. Chng could have been jailed for up to one year and/or fined up to $5,000.