The serviceman had been on patrol in Kajaki, Helmand province
A Royal Marine has been killed by a blast in southern Afghanistan, the Ministry of Defence said.
He served with 45 Commando, based in Arbroath, the MoD added.
Cder Paula Rowe, from Task Force Helmand, said: "Our thoughts and prayers are with his family and friends at this dreadful time."
His death took the number of British armed forces personnel killed in Afghanistan since operations began in October 2001 to 126.
In a statement, the MoD said the marine was struck by an explosion during a patrol of the Kajaki area of Helmand province.
He received medical treatment at the scene, but died as he was taken to the military hospital at Camp Bastion.
Brig Gen Richard Blanchette, of the International Security Assistance Force (Isaf), offered his condolences to the serviceman's family.
He said: "This man died serving his country and the people of Afghanistan; he died a hero."