Wayne Mapp, defence minister at the time of a raid in Afghanistan conducted by New Zealand soldiers alleged to have killed and injured innocent people, believes it is "not enough to say there might have been civilian casualties," and has called for further investigation.

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The journalists Nicky Hager and Jon Stephenson brought the allegations to light in their book Hit & Run, which tells of an operation in Tirgiran Valley, Afghanistan in August 2010 which they say caused injured fifteen civilians and killed six, including a three-year-old girl named Fatima.

The New Zealand Defence Force and the government have strongly contested the book's claims, saying that SAS soldiers acted professionally and nine "insurgents" were killed in the raid. Defence Force chief Lt. Gen. Tim Keating has said there "may have been" civilian casualties.

Mapp, who approved Operation Burnham, has clarified his position today in a column for the website Pundit, saying he had "no doubt that New Zealand soldiers act to the highest ethical standards."

However, he writes, "the law of armed conflict accepts that civilian casualties might occur in military operations, and in many cases there is no legal liability for them, particularly if they were accidental."

"For me, it is not enough to say there might have been civilian casualties. As a nation we owe it to ourselves to find out, to the extent reasonably possible, if civilian casualties did occur, and if they did, to properly acknowledge that."

Mapp writes that if there were civilian casualties, compensation should be provided, because "it is part of Afghan culture that compensation is made in recognition of loss.This is a process of restorative justice, rather than determining liability."

But Mapp stopped short of arguing for a full independent inquiry, instead saying that reliable information could be gleaned "through diplomatic approaches to the Afghan government, and trusted NGO’s on the ground."

Prime Minister Bill English turned down the idea of holding an inquiry into the Hit & Run allegations, in defiance of opposition parties, human rights lawyers, and the book's authors.