Six soldiers killed in Afghanistan on Friday have been named, as ministers came out to defend UK policy after losing 15 men in just 10 days.
Five members of the County Down-based 2nd Battalion The Rifles died in two explosions near Sangin, Helmand.
They were: Cpl Jonathan Horne, and Riflemen Joseph Murphy, Daniel Simpson, William Aldridge and James Backhouse.
A 2nd Royal Tank Regiment corporal killed in an explosion near Nad Ali was named as Lee Scott, 26, from Norfolk.
Lt Col Robert Thomson, commanding officer of 2 Rifles, said it had been a "grim day" in Sangin as they honoured their dead - three of them aged 18.
"We all knew that each one of those Riflemen would have wanted us to 'crack on'.
"And that is what we shall do - there will be no turning; the work is too important.
We are profoundly grateful for the sacrifices your brave soldiers make for us
Helmand Governor Gulab Managal
"They lived and fought alongside us and tonight our lives are much worse for them not being here. But we can celebrate what they were and what they achieved. We are so very proud of them."
Cpl Horne, 28, from Walsall, West Midlands, had been in the army since 2004. He leaves a wife, Rachel and two children Frankie and Jessica.
Rifleman Murphy, 18, from Castle Bromwich, Birmingham, had been carrying wounded "battle-buddy" Rifleman Simpson to safety when killed by a makeshift bomb, the Ministry of Defence said.
Rifleman Simpson, 20, from Croydon, south London, also died in the explosion. He had an eight-month-old son, Alfie.
The two remaining victims were also 18. Rifleman Aldridge, from Bromyard, Herefordshire, was one of the youngest soldiers deployed in Helmand, having come of age on 23 May.
Rifleman Backhouse, from Castleford, west Yorkshire, was just a few months older.
Governor of Helmand Province Gulab Managal offered condolences to the soldiers' families on behalf of the people of Helmand.
He said: "Your sorrow is our sorrow.
"We are profoundly grateful for the sacrifices your brave soldiers make for us because we know that they fight to give us, and our children, a future free of tyranny and fear.
"They did not die in vain. It is a debt we will never forget."
Prime Minister Gordon Brown has insisted the mission is showing "signs of success", as the government rebuffs claims troops have been left ill-equipped and short of manpower.
Former Tory defence secretary Lord King had suggested there was a "critical shortage" of helicopters in Helmand
Click to view image: 'MOD names 6 killed'
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