TRAINING the Afghan police, as well as the Afghan army, so that they can eventually take over responsibility for their country’s security, is at the heart of Nato’s exit strategy for allied troops.

And that strategy suffered a very serious blow yesterday when a “rogue” Afghan policeman gunned down and killed five British soldiers in Helmand.

How can our troops ever reach the end of their mission in Afghanistan if, as is feared, the Taliban has infiltrated the Afghan police?

How many more rogue policemen might there be, waiting to shatter Nato’s planning for a withdrawal?

These are questions which are bound to fuel mounting concerns that the complex challenge in Afghanistan can never be met; that it is time to bring our soldiers home and thank them for their efforts.

We understand those concerns but to pull out now would leave Afghanistan and its neighbours in an unthinkable position.

It is the easier, more popular, option but we do not believe it is the time for knee-jerk reactions to what is, for all we know, an isolated incident.

The Taliban’s biggest fear remains that Afghanistan becomes strong enough to police itself, and that must remain the key objective.

The deaths of another five of our soldiers is a terrible loss, bringing the number of British troops killed in Afghanistan this year to 92.

In the week leading up to Remembrance Sunday, it is a sad and timely reminder of the importance of remembering the courage and sacrifice of those serving in the war zone of Helmand.