The most senior British officer to be killed in Afghanistan is being laid to rest. Lieutenant Colonel Rupert Thorneloe MBE, Commanding Officer 1st Battalion Welsh Guards from Kirtlington, Oxford, died in an explosion on July 1 alongside 18-year-old Trooper Joshua Hammond. They both perished when an improvised explosive device (IED) was detonated under their Viking armoured vehicle. Lt Col Thorneloe's funeral service will be held at the Guards Chapel at London's Wellington Barracks. His family said they had been comforted by the tributes that poured in following the 39-year-old father-of-two's death. The Prince of Wales - who is said to have known him well - is among those who have written to express condolences. He has said of the death: "It's completely heartbreaking. The whole battalion is suffering." Prime Minister Gordon Brown said: "Lt Col Thorneloe was someone I know, someone I worked with, someone I admired." Lt Col Thorneloe's father, Major (retired) John Thorneloe said: "As the father of Rupert I would like, on behalf of Rupert's wife, Sally, Rupert's mother Veronica, our families and myself, to record our appreciation for the overwhelming support and tributes we have experienced since Rupert was tragically killed in Afghanistan on Wednesday, July 1."