A British soldier has been killed overnight in the southern Helmand province of Afghanistan, the Ministry of Defence (MoD) said.
The MoD said the soldier, from 14 Signal Regiment based in Pembrokeshire, was "shot and killed" in a clash with "enemy insurgents" in northern Helmand.
The ministry said the soldier was killed during an attack on a platoon house where troops were based.
The soldier brings the number of UK fatalities there since 2001 to 21.
Afghanistan is going through its bloodiest period since the fall of the Taleban five years ago. Eight British soldiers have died there this month alone.
A MoD spokeswoman said: "It is with regret that the MoD can confirm the death of a British soldier from 14 Signal Regiment following an attack on the platoon house in Musa Qaleh, northern Helmand, Afghanistan, in the early hours of this morning.
"The soldier died immediately of wounds sustained during the attack. No other UK or friendly forces were injured in the incident."
The soldier's unit, 14 Signal Regiment, is based at Cawdor Barracks, Brawdy, Pembrokeshire, and specialises in electronic warfare, including the jamming of radio signals.
Eight troops have died in Afghanistan this month
Brigadier Ed Butler, commander of the UK taskforce in Helmand, defended the British presence in Afghanistan, but said soldiers still face tough challenges.
"The current tempo of operations in Northern Helmand, including those in Musa Qaleh, is demanding, but manageable," he said.
"The Taleban are a determined enemy, and the challenge of bringing security to Musa Qaleh is a continuing one. But we are on well on track to succeed."
"We are making good progress in helping to bring security to areas that have had little by way of law and order for over 30 years, most recently with the establishment of a large number of Afghan police in the heart of the town."