Town Council and HDB
I just spoke to a woman who said that an officer had come to her home while she was away. Her husband answered the door. The woman said that she could not keep cats in her flat. I asked her for more details as she said the woman was from the town council and not from the HDB. She called them up and it turned out the TC had not been by. The only thing she knew was that the officer was a woman with short hair.
She did not know what the town council did, nor the HDB. In a nutshell, the town council takes care of the surrounding environment - the walkways, the corridors, void decks, etc. The HDB takes care of the flats - and the flats contrary to popular belief aren't actually owned by the flat 'owner' even if the person has bought it. The flats are rented - and that's why the HDB can impose conditions such as no cats within the flats as the landlord.
If someone does come by, make sure to ask for a card or some form of identification so you know whom the person is.
Off to deliver more traps.