A soldier from 1st Battalion Grenadier Guards has been killed in Afghanistan while on sentry duty, the Ministry of Defence said.
The soldier was serving in the Nahr-e Saraj district of Helmand Province when he was killed by "enemy action" on Friday.
Next of kin have been informed and asked for a 24-hour period before further details are released.
Major Ian Lawrence, spokesman for Task Force Helmand, said: "It is with great sadness I must inform you that a soldier from 1st Battalion Grenadier Guards has been killed whilst 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."