THE most senior British Army officer to be killed in action since the Falklands War was described as "a born soldier" who was "destined for greatness".

Lieutenant Colonel Rupert Thorneloe, commanding officer of the 1st Battalion Welsh Guards, was killed near Lashkar Gah in Helmand province, southern Afghanistan, on Wednesday.

The Prince of Wales, who is Colonel of the Welsh Guards, was "deeply saddened" by his death, a Clarence House spokesman said. It is understood Charles knew him well.

Lt Col Thorneloe, of Kirtlington, near Oxford, was killed along with 18-year-old Trooper Joshua Hammond, of 2nd Royal Tank Regiment, who was described by senior officers as "a superb soldier".

General Sir Richard Dannatt, Chief of the General Staff, said the commanding officer was at the "leading edge of his generation" while his wife Sally said the 39-year-old father-of-two would be "sorely missed".

He had left the Battle Group Headquarters and was in a resupply convoy in order to visit his men who were conducting a major operation in hostile territory, the Ministry of Defence (MoD) said.

An improvised explosive device (IED) was detonated under his Viking armoured vehicle at about 3.20pm local time, taking the number of UK servicemen and women who have died in Afghanistan since operations began in October 2001 to 171.

Gen Sir Richard said his death was "a devastating blow to the Welsh Guards Battle Group and to the Army as a whole".

A MoD spokesman said he was not aware of any specific investigation into why Lt Col Thorneloe was travelling in a Viking vehicle, but said all deaths in Afghanistan were investigated.

The Viking was introduced into Afghanistan three years ago but last year the MoD admitted it had reached the limit of how much it could be armoured following a series of deaths involving Taliban IEDs. It is due to be replaced by the new Warthog vehicle next year.

Lt Col Thorneloe's wife Sally said he was her "very best friend" and added: "Our daughters Hannah and Sophie will have to grow up without their Daddy, although I will see a part of him in them every day.

"I could not have asked for a more caring, adoring and loving husband and father."

She said their lives would never be the same again.

Describing her husband as "a born soldier" and "an inspiration", she said: "I know he led from the front and would not have had it any other way. He cared deeply about his men as he did about so many.

"His charisma, compassion and enthusiasm for all in life will be so sorely missed by his family and many friends but most of all by me who loved him so much."