The death takes the number of British troops killed in Afghanistan to 286
A British marine from 40 Commando Royal Marines has been killed in Afghanistan, the Ministry of Defence has said.
The marine, who was serving as part of Combined Forces Sangin, Helmand, was killed in an explosion near Patrol Base Almas, in Sangin, on Friday morning.
He died while on a joint foot patrol with the Afghan National Army to reassure and improve the security to the local population, the MoD said.
Next of kin have been informed of the marine's death.
The death takes the total number of British service personnel killed in Afghanistan to 286.
Lieutenant Colonel James Carr-Smith, spokesman for Task Force Helmand, said: "It is my sad duty to inform you that a marine from 40 Commando Royal Marines was killed by an explosion this morning in Sangin.
'Doing his duty'
"He was conducting reassurance operations with the Afghan National Army when he was struck by an explosion.
"He died a marine, doing his duty alongside his British and Afghan comrades. His actions will not be forgotten and we will always remember him."
Earlier, the Ministry of Defence announced that about 8,000 British forces based in Helmand are to come under the operational command of the US.
The move is part of a restructuring of Nato forces, with command and control in southern Afghanistan split into two.
The UK's Maj Gen Nick Carter will now oversee Kandahar, while Maj Gen Richard Mills from the US will take on Helmand.
The command of the 1,100-strong British battle group based in Sangin - an area which has seen a number of UK deaths recently - and in Kajaki will also come under US-led force from 1 June.
The UK force level in Afghanistan is currently 9,500, but with special forces totals some 10,000.