Tensions are running high and violence could break out at any time in many of the areas which British paratroopers are trying to make safe for returning refugees.

Gunfire has been reported between Albanian and Serb communities, and British patrols themselves have come under fire.

On one occasion soldiers were fired at while they dealt with an incident in which a Serb was shot dead.

Diplomacy not enough

Most of the time, diplomatic skills are needed to diffuse potentially explosive incidents. But sometimes, more is needed.

On Wednesday, British soldiers shot dead a man in Kosovo after he came towards them brandishing a weapon, according to the Ministry of Defence.

An MoD spokesman said the soldiers shouted a warning but the man made as if to fire at them.

Before K-For troops moved into Kosovo, each soldier was given a copy of the rules of engagement explaining the circumstances in which guns could and could not be used.

A senior British military source told The Daily Telegraph recently that the rules allow the troops to act "robustly, decisively but impartially".

Verbal warning

Almost all the British troops in Kosovo have carried out a tour of duty in Northern Ireland, which will have prepared them for dealing with daily encounters between armed groups across the Serb-Albanian ethnic divide.

The rules of engagement in Kosovo are similar to those used in Northern Ireland. All K-For soldiers carry a Green Card, allowing them to kill in self defence, but only after a verbal warning has been given.

British Army soldiers are trained in Northern Ireland to a required standard called the Yellow Card. This specifies when minimum force can be used and when lethal force can be used as a last resort.

A soldier may fire if he perceives himself, a colleague or civilian, to be in imminent danger. He must identify a weapon, such as a firearm or a car running a roadblock if it is driving at a civilian or soldier or has terrorists on board.

Soldiers in Northern Ireland are trained to shoot to kill, not to injure someone. But this training can only come into effect when all other avenues have been closed.

A soldier is only allowed to open fire if he or she is in danger and there is no other way to deal with the situation.