Not until a thorough investigation has been carried out can there be certainty what caused the series of explosions in a Wong Tai Sin garage that killed three people and injured nine others, one critically. Perhaps the blasts are related to the liquefied petroleum gas (LPG) tank of the taxi that had just pulled up for repairs or maybe there is something sinister at play. Whatever the reason, the promptness of emergency services in getting to the scene surely prevented the number of casualties from being higher. But as always, after there have been needless deaths, questions have to be raised as to whether the tragedy could have been avoided.

Killed were the owners of the garage and a neighbouring glass shop and the taxi driver. Among the injured were residents of the 22 flats above the garage. Dozens of people, including 99 from a nearby elderly care centre, were evacuated. A vehicle repair shop is an unusual feature for a residential area in many other cities, but not in Hong Kong - it is more often than not inevitable in a place so crowded and compact.

In older districts, garages and repair shops are often found on the ground floors of residential blocks. It is not unusual in some areas to find schools or homes for the elderly next to petrol stations. Limited land area requires such concessions, which in turn means that laws regulating the operation of such businesses have to be sturdy and strictly enforced. The rarity of accidents is evidence that the rules are working and government inspectors are doing a good job.