A British soldier from 1st Battalion Grenadier Guards has been killed in Afghanistan while on sentry duty, the Ministry of Defence has said.
The soldier was serving in the Nahr-e Saraj district of Helmand province when he was killed by "enemy action" on Friday.
His next of kin have been informed; they asked for a 24-hour period before further details are released.
Major Ian Lawrence, a spokesman for Task Force Helmand, said on Saturday: "It is with great sadness I must inform you that a soldier from 1st Battalion Grenadier Guards has been killed while on sentry duty in the Nahr-e Saraj district of Helmand province.
"The thoughts and prayers of everyone in the task force are with his family and friends at this very difficult time."
The soldier's death brings the number of members of UK forces to have died since operations in Afghanistan began in October 2001 to 425.