Outram MRT Shooting Incident

I was horrified when i read today's Straits Times frontpage - a murder suspect was shot dead by a policeman at Outram MRT yesterday afternoon. Why? This is the first time in the history of Singapore that police opened fire and killed a man in an MRT Station where there are lots of commuters taking the trains.
However, from the policeman's point of view, he did it out of self-defence as the murder suspect attempted to attack him with a knife.
I felt strongly that the policeman should have just shot him in the leg to take him down rather than fire point blank at his chest, killing him.