AFGHAN ASSASSIN KILLS 5 SOLDIERS; ROGUE POLICEMAN OPENS FIRE ON TROOPS INSIDE COMPOUND; VICTIMS HAD TAKEN OFF THEIR HELMETS AND BODY ARMOUR; Taliban switch tactics to strike against soldiers on training duty.

Byline: Ross Lydall and Nicholas Cecil

FIVE British soldiers were killed and five others wounded when a rogue member of the Afghan national police opened fire without warning in a police station, the Ministry of Defence said today.

The men, from the Grenadier Guards and Military Police, were off duty and had removed their body armour and helmets in the courtyard of the station in the Nad-e'Ali district of Helmand Province yesterday.

A man armed with an AK-47 and dressed in an Afghan uniform began firing and fled before anyone could respond. It takes the total of British deaths in Afghanistan to 229 and makes this year the worst for loss of military lives since the Falklands with 92 killed.

The targeted killings marks a chilling change of tactics from roadside bomb attacks. One of the dead men is thought to be a senior figure but not an officer. British soldiers in the area had been involved in building bridges in the area and mentoring the Afghan army.

Nad-e'Ali district is known to the British troops as "the Wild West". Gordon Brown said the outrage was a "terrible loss". Mr Brown said: "My thoughts, condolences and sympathies go to their families, loved ones and colleagues. I know that the whole country too will mourn their loss."

The attack equals the previous worst loss in a single incident, when five members of 2nd Battalion The Rifles died in bomb attacks in Sangin in July.

The incident could mark a remarkable switch in tactics by the Taliban with them apparently now opting for carefully targeted assassinations and ambushes inside previously secure zones.

It presents new headaches for the new British commander, Brigadier Janes Cowan. He now has to revise all appraisals of his Afghan allies in the army units and particularly the national police.

Ministry of Defence sources today said another possible motive for the attack was that the man who opened fire may have been involved in an internal dispute with his commanders. The Ministry of Defence said next of kin had been informed. The soldiers will not be named until tomorrow.

Lt Col David Wakefield, spokesman for Task Force Helmand said: "Five British soldiers, five of our own, shot down in the course of their duty. They will not be forgotten."

In a blog from Helmand last month, the commanding officer of the 1st Battalion Grenadier Guards, Lt Col Roly Walker, said forces had been preparing to tackle counter insurgencies, training alongside the Afghan National Army and US forces.

Lt Col Walker said that "every man and woman will need to stay focused on the job" and alert. He added: "Operation Herrick is a demanding and dangerous operation."

Mentoring the Afghan army is a key part of Britain's strategy of eventually withdrawing from Afghanistan. This can only happen when Afghan forces are themselves able to tackle the Taliban and uphold the wishes of the national government.

The Grenadier Guards had only been in the country for about two weeks. At least 10 of the soldiers are thought to have been present at a meeting, known as a "shura", with police officers and possibly local elders as they sought to improve relations.

There are around 9,000 British soldiers in the country, with the Prime Minister under pressure to send more if President Obama orders a surge of around 40,000 US forces.

Earlier this week Hamid Karzai was re-elected president after plans for a second round run-off were abandoned when his main challenger Dr Abdullah Abdullah withdrew from the contest.

Mr Brown said today of the British soldiers: "They fought to make Afghanistan more secure.

"But above all to make Britain safer from the terrorism and extremism which continues to threaten us from the border areas of Afghanistan and Pakistan.

"I pay tribute to their courage, skill and determination. They will never be forgotten.

"It is my highest priority to ensure our heroic troops have the best possible support and equipment -and the right strategy."

CAPTION(S):

In the line of fire: Grenadier Guards on patrol in Helmand province. Three of the dead were Guards, the other two were military policemen