Britain’s increasing use of women on the front line of war was called into question yesterday after Afghanistan claimed its first female casualty.

The intelligence officer, named last night as Sarah Bryant, 26, was on a secret counter-terrorism mission in Helmand province when she was killed along with three reserve members of the Special Air Service when their armoured Land Rovers were hit by a roadside bomb.

It was the greatest single loss of life for the Territorial Army since the Second World War and the biggest single loss of life for British troops since September 2006, when 14 personnel were killed in an RAF Nimrod crash near Kandahar. It brings to nine the number of British soldiers killed in Afghanistan in as many days.

The reservists, from the 23rd SAS Regiment, were providing support for an operation by the Afghan National Police east of Lashkar Gah.

Ms Bryant, whose family live in Carlisle, married a fellow intelligence officer two years ago. Her work in Afghanistan involved monitoring Taleban telephone and walkie-talkie communications. She spoke the local Pashtu language and was recently promoted to the rank of sergeant in the Intelligence Corps. She had done two six-month tours to Iraq.

Her father, Des Feely, said that he and his wife Maureen were “absolutely devastated to have lost the beautiful daughter we adored”. He added: “But I know that at least Sarah died doing the job she loved and for a cause she believed in.”

He said that she had been due to fly home next month. “But now she’ll be coming back to be buried with military honours at the church in Wetheral where she was married two years ago.”

Her death has highlighted the changing role of women soldiers on the “asymmetric battlefields” of Afghanistan and Iraq, where the traditional concepts of frontline and support roles have become blurred.

Commanding officers said that soldiers were now routinely selected for operations regardless of their gender.About a fifth of the 8,000 Service personnel in Afghanistan are women, even though they make up just a tenth of total army numbers. Army rules forbid the deployment of women in operations where they would be expected to “close with and kill the enemy”. But senior officers said last night that all operations outside base camps could be regarded as on the front line.

Gerald Howarth, the Shadow Defence Minister, called on the Government to make clear its position on the role of women in frontline positions. “There is no doubt in my mind that the Government needs to clarify that it is adhering to its own guidelines,” he told The Times. He added that the guidelines needed to be “appropriate to the shifting nature of the threat in Afghanistan”.

Major Bruce Spencer, a British military spokesman in Lashkar Gah, told The Times that the woman officer killed had been chosen for the patrol because she had the necessary skill set. “Military campaigns have moved on from the days when we confronted the enemy in the trenches across a clear front line,” he said. “We now have an asymmetric battlefield. The front line could be right outside the camp gates or 50 miles away. We select people on the basis of what they can do, not on the basis of their gender. Women are part of the full panoply of the Armed Forces. The risks that they take are the same as anyone else, and they understand the risks.”

Nick Harvey, the Liberal Democrat defence spokesman, said: “Obviously an inquiry will establish if there has been any breach of the rules of engagement in this instance. However, the reality of modern warfare is that men and women are together in harm’s way and I have nothing but admiration for this woman fighting for her country.”

Patrick Mercer, the Tory MP and former soldier, said that women were now routinely on the front line. “There is no reason a forward operations unit should not have a female radio operator. The intelligence corps are a combat arm, so there is nothing wrong with that. I don’t necessarily like it very much. But she signed up.”

Gordon Brown expressed his “deepest condolences” to the families of the four soldiers. Des Browne, the Defence Secretary, rejected suggestions that British troops in Afghanistan could start “losing heart” after the recent surge in casualties.

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