Two British soldiers involved in a long-range reconnaissance patrol along the border between Iraq and Iran were killed by a huge roadside bomb today which ripped through their Scimitar armoured vehicle.

Another soldier in the same Scimitar was “very seriously injured” and his condition was described as “critical”.

Two other soldiers in a second Scimitar were also injured in the blast which took place not far from Camp Sparrowhawk in Maysan province where only the day before the British had handed over security control of the area to the Iraqis in a special ceremony.

The soldiers who died were serving with The Queen’s Royal Lancers battle group. The battle group is due to be replaced from next month by another unit which will include Prince Harry’s A Squadron Blues and Royals of the Household Cavalry.

Prince Harry - 2nd Lieutenant (Cornet) Wales - is now fully trained as a troop leader to take command of four Scimitars and will be deploying to Iraq with his men.

The explosive device which killed the two soldiers at about 11am may have been of the more advanced kind which the Americans and British believe are being smuggled over the border from Iran.

A British Army spokesman said: “The three injured soldiers were evacuated by helicopter to a coalition military medical facility at Tallil in the province of Dhi Qar. The seriously injured soldier was in intensive care."

The two deaths increase the total British fatalities in Iraq since March 2003 to 144, of whom 111 died as a result of enemy action. Also, since January last year, 158 British servicemen, including the three in today’s incident, have been wounded in action. This compares with 111 injured from enemy action between January 2003 and December 2005.

The latest fatalities came only four days after the mid-air collision between two RAF Puma helicopters north of Baghdad in which two military personnel were killed, Colour Sergeant Mark Powell of the SAS and Sergeant Mark McLaren of the RAF.

Although security for Maysan was taken over by the Iraqis on Wednesday, there are still about 400 British soldiers in the province, all engaged in long-range reconnaissance along the border. The Iraqis asked the British to continue monitoring the border, and this role is likely to remain a British responsibility throughout the six months in which Prince Harry is serving in Iraq.

During the handover ceremony on Wednesday at Camp Sparrowhawk, an Iraqi Army base near the provincial capital, al-Amarah, Major-General Jonathan Shaw, General Officer Commanding Multinational Division Southeast, said it was “a moment of optimism”.

He said he was optimistic because the handover of two other provinces previously controlled by the British, at al-Muthanna and Dhi Qar, had “demonstrated to the rest of Iraq what can be achieved”.

In Maysan the British withdrew from their permanent base at Camp Abu Naji near al-Amarah last August, and focused all their efforts on patrolling the border areas. The handover of Maysan to the Iraqi Army 10th Division is not expected to lead to any reduction in the British presence in the province.

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