When told not to rest his feet on a bus seat, a man explained that he had a problem with his knee.
But things got heated when the commuter proceeded to record him on camera.
The incident took place on board bus service 961 along Woodlands Road on Saturday (April 9) around 5.40pm.
The commuter, who shared a video of the encounter with Stomp under the name Stephen, said he approached the man and asked him if he had seen the sign telling commuters not to rest their feet on the bus seats.
In the video, the man can be seen with both his legs propped up on the seat in front of him.
The man responded, "My knee problem what," to which Stephen replied, "Okay, you tell the doctor."
When he realises he is being filmed, the man later exclaims: "People tired, people knee problem, you take picture. Go and take everybody lah, better."
Said Stephen: "This man refused to put his legs down even after I told him to. You can hear me talking to him politely at the start of the video.
"He also said, 'Bus captain also never say anything, you so busybody for what?' I was saddened as he even called me a b*****d, but it was not recorded.
"If signs are put up but not enforced, what is the point?"