Afghan National Army Major General, Sayeed Malook, 215th Corps commander, has said he is "deeply upset" by death of a British serviceman in a so-called 'inside attack' yesterday.
"Regrettably despite all our efforts to prevent incidents such as these last night we missed one of these again.
"I'm deeply upset and heartbroken at this. We will focus all our efforts towards preventing these incidents.
"I would like to express my condolences to the families and relatives, and I would also like to wish good health to those who have be wounded in this incident", he added.
More top news
Arthur Simpson-Kent, 48, admitted killing Ms Blake and their sons according to his lawyer.
Two brothers have been arrested on suspicion of murder after their parents were found dead in their own home over the weekend.
The first man to be convicted of murder on the basis of DNA evidence should be moved to an open prison, according to the Parole Board.