When CNA arrived at the scene on Tuesday afternoon, four police officers were outside the unit, which was cordoned off with police tape on both sides.
A black body bag was carried out of the unit at 5.33pm by two police officers and two employees of Singapore Casket.
A neighbour told CNA that she saw a big-sized bald man in a blue T-shirt seated at the end of the corridor when she returned from the market at around 11.15am. She added that she saw multiple black bags outside the unit.
Another neighbour said that the bespectacled man was sitting on a stool and handcuffed behind his back.
She said that two men and two women lived in the unit, adding that she sometimes heard shouting or a harsh tone from a man but did not hear anything from the flat on Monday.
According to another neighbour, the door to the unit was always closed.
Police investigations are ongoing.
