Once again, terrorism has struck the heart of a world capital ("Paris lockdown after terror attacks"; Nov 15).

Once again, shootings have taken place, and with much more deadly effect.

All this points to a pushback by the Islamic State in Iraq and Syria (ISIS) as outside forces pound its positions.

These attacks are to be expected. It is the price to be paid for taking on ISIS.

But how can one guard against reprisals and prevent them from happening?

In the case of the latest attack in Paris, it is difficult to determine anything. The details seem sketchy as the authorities deal with the chaos that followed.

This is why intelligence on the ground is so important, as well as intelligence sharing between countries.

This is a timely reminder to Singaporeans that we should not take our stability as a given.

It is with much trepidation that I view the situation outside our country, and the threats that loom in our nearest and larger neighbours, Malaysia and Indonesia ("Malaysian militants plan to start ISIS faction in S-E Asia"; Nov 15).

Local groups there are swearing allegiance to ISIS, and have warned that Singapore is a target.

This cannot be taken lightly. Security has to be stepped up, with everyone on the alert for suspicious activity.

It is also important that our neighbours do everything in their power to stop these groups from gaining strength.

They are Singapore's first line of defence against these elements. We can only hope that they succeed and prevent these groups from getting close to our home and inflicting harm on our citizens.

Manoraj Rajathurai