Prince Charles described the death of Lieutenant-Colonel Rupert Thorneloe in Afghanistan as "heartbreaking" while Prime Minister Gordon Brown said he knew and "admired" him.

Lt-Col Thorneloe, commanding officer of the 1st battalion of the Welsh Guards, was killed in a blast which hit his Viking armoured vehicle near Lashkar Gah in Helmand province, southern Afghanistan, on Wednesday.

Another soldier, Trooper Joshua Hammond, 18, of 2nd Royal Tank Regiment, also died in the explosion.

Prince Charles is colonel-in-chief of Lt-Col Thorneloe's regiment and knew the officer.

During a visit to Cornwall, he said he was "mortified" when he heard of the deaths.

"I was horrified, to say the least, about both deaths, Trooper Hammond as well," he said.

"Having been to visit the Welsh Guards at Aldershot before they left to go to Afghanistan, having met the families and having met Col Rupert's wife, my heart is very much with them.

"It's completely heartbreaking. The whole battalion is suffering.

"To lose a commanding officer who was such an inspiring person is an awful tragedy."

The Prime Minister, speaking on a visit to the Christie Hospital in Manchester, said: "I think the whole country will be mourning today the deaths of Lt-Col Rupert Thorneloe and Trooper Joshua Hammond.

"They were very professional soldiers, they were serving in Afghanistan in the most difficult terrain.

"Lt-Col Thorneloe was someone I know, someone I worked with, someone I admired."

According to Defence Secretary Bob Ainsworth, "born soldier" Lt-Col Thorneloe believed
in the UK's mission in Afghanistan and was "destined for greatness".

Mr Ainsworth said: "It'll have quite an impact on the men who work directly under him and they really will be going through it, having lost the boss, so people have got to lift them."