I read with some concern the news report as well as the Forum letter (Cause of chemical stench still a mystery, and Poor show by authorities over mystery smell; both on Sept 27).

It appears that both the National Environment Agency (NEA) and Singapore Civil Defence Force (SCDF) are still unable to get to the bottom of what caused the smell and smoky conditions in several parts of Singapore.

This is worrying especially in this heightened security climate as it exposes the potential weaknesses of Singapore's responding agencies to a chemical attack.

Who knows if this was a test by hostile forces on the security climate in Singapore?

If the authorities cannot determine the cause of the conditions then who can?

Such conditions would not occur on their own without a plausible reason.

In any case, which would be the rightful authority to investigate and update Singaporeans on this matter? Would it be the NEA or SCDF?

I hope The Straits Times will continue its coverage of this matter until satisfactory answers can be provided by the authorities.

Adrian Soh Mun Wai