Tributes were paid on Thursday to the four British soldiers who died in a roadside explosion in southern Afghanistan, taking the death toll since 2001 to 106.

Sergeant Sarah Byrant, 26, was described as a hero by her husband, also a soldier, after she became the first female officer to die in combat in Afghanistan.

"My wife was a truly special person," Corporal Carl Bryant said in a statement. "She was funny, kind and the most amazing person to be around, I will never stop being thankful for the time I spent as her husband."

Byrant was an accomplished horsewoman who had completed two six-month tours in Iraq. She was recently promoted to the rank of sergeant in the Intelligence Corps.

She spoke the local Pashtu language, while her work involved monitoring Taliban telephone and other form of communications.

The other three soldiers who died were named by the Ministry of Defence as Corporal Sean Robert Reeve, 28, Lance Corporal Richard Larkin, 39, and Paul Stout, 31.

They were killed on Tuesday when the vehicle they were travelling in was hit by an explosion.

The soldiers were taking part in an operation east of Lashkar Gah in Helmand province, the Ministry of Defence said.

A fifth soldier injured in the blast is in a stable condition.

Defence Secretary Des Browne said: "All four were immensely dedicated and professional service personnel and my sincere and deepest condolences go out to all of their family and loved ones.

"I cannot comprehend the pain they are going through. They have made the ultimate sacrifice, laying down their life alongside those of their comrades in pursuit of the aim of a peaceful and stable Afghanistan. We will ensure their losses were not in vain."

The deaths follow those of five members of the Parachute Regiment in two separate incidents last week.

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