The 17th floor of this block of Housing Board flats in Punggol looked normal and quiet. But I was there to chase a story about neighbour disputes and, within minutes, the tension was palpable.

I knocked on one resident's door. He showed me a video of his neighbour on his mobile phone. It showed a woman dragging a metal rod along the HDB flat corridor. "Be careful when you approach her for an interview," he warned.