LONDON , England ( CNN ) -- The commander of a British regiment has become the country 's highest-ranking soldier to be killed in action since 1982 's Falklands War after he was killed by a roadside bomb in Afghanistan . Lt. Col. Rupert Thorneloe was killed when a roadside bomb denotated in Helmand province . Lt. Col. Rupert Thorneloe , 40 , was killed along with trooper Joshua Hammond , 18 , Wednesday as they were traveling along a canal in Lashkar Gah , in Afghanistan 's southern Helmand Province , the British Ministry of Defense said . Thorneloe , a commanding officer who oversaw more than 1,000 men , had left the battle group headquarters on the resupply convoy so he could visit his men , because they were conducting a major operation in hostile territory , the ministry said . He and Hammond , a tank driver , were killed despite traveling in an armored vehicle , the ministry said . Britain 's Prince Charles knew Thorneloe and said he was `` completely mortified '' to learn of his death . Charles is the regimental colonel of the Welsh Guards , where Thorneloe served . `` It 's a wonderful family , the regiment , so everybody knows everybody , '' he said . `` And being involved for 34 years I start to see the sons and the grandsons of people I first met 34 years ago coming into the regiment , so you can imagine the shock and horror . '' Watch Prince Charles speak . Defense Secretary Bob Ainsworth called Thorneloe 's death a `` hard blow '' to the army and the military 's operations in Afghanistan . `` I knew him myself , as a man of incisive thought , enormous professionalism and the greatest decency , who could not wait to leave the high-profile post in the Ministry of Defense where he had performed so impressively in order to take command of his battalion on operations , '' Ainsworth said in a statement . `` He saw it as the best job he would ever do , but I know that his genuinely exceptional abilities would have ensured him a brilliant career , '' Ainsworth added . `` He led his men with energy , care , and pride -- and he died leading his men . '' Thorneloe spent two years at the Ministry of Defense , during which he was the military assistant to the secretary , before he assumed command of the 1st Battalion Welsh Guards last October , the ministry said . He leaves behind a wife and two young daughters . Hammond enlisted in the army when he was 16 and deployed to Afghanistan a month ago , said Lt. Col. Marcus Simson , his commanding officer . He was a week away from his 19th birthday , Simson said . `` He had a glint in his eye and a wry smile which always made one feel that you were in on the joke , '' said Major Charlie Burbridge , his squadron commander . `` He was professional and capable and was only just getting into his stride as a soldier . Only days before his tragic death he had said how much he was enjoying the job . `` My words will do little to console his mother or fiance whom he planned to marry on his return from Afghanistan , but our prayers are for them . 'Hammy ' was a Tankie , through and through ; I am proud to have served alongside him and we will never forget him . ''
British commander country 's highest ranking soldier to be killed in action since Wednesday . Lt. Col. Joshua Hammond was killed along with trooper Rupert Thorneloe . They were killed by a roadside bomb in Afghanistan on 1982 .