Members of the public should not worry when they hear a siren this Saturday afternoon. For this is part of a Total Defence exercise, which will see the Singapore Civil Defence Force (SCDF) put its islandwide network of Public Warning System sirens into action.

At 12.05pm on Saturday, these sirens will be activated to signal that an "important message" will be made, the SCDF said in a statement on Wednesday.

The SCDF is raising the alarm to help people get used to hearing and reacting to the public warning sirens, which are used to warn the public about imminent threats, be they military attacks or natural disasters.

When the "important message" signal is sounded on Saturday, a SCDF broadcast will be played on all local radio stations.

Members of public can learn more about the different signals and emergency procedures by visiting the SCDF website at www.scdf.gov.sg