According to Gunaseelan, he had just broken up with his girlfriend in July 2916, and was feeling down. On 30 July, he had drinks with another friend near Central Mall. The duo then proceeded to Liang Court, where they met another friend. Gunaseelan found a foldable knife in the toilet and kept it. Subsequently, the trio walked towards Raffles City to have supper at McDonald's. As they passed by the Treasury Building, Gunaseelan used the knife to slash a red National Day banner that was fixed to a pillar.