A British soldier has been killed in what is believed to be an insider attack by a member of the Afghan National Army.
The solider, who was from 28 Engineer Regiment, was shot dead in the Nahr-e Saraj district of Helmand province.
The attack took place on Monday when the suspect turned his weapon on ANA and International Security Assistance Force soliders.
A number of other people were injured during the attack. According to the BBC, the Taliban has claimed responsibility in a statement.
Major Laurence Roche, spokesman for the Task Force Helmand, said: "It is my painful duty to report the death of a soldier from 28 Engineer Regiment, who was shot and killed by a suspected member of the Afghan National Army at a patrol base in the Nahr-e Saraj district of Helmand Province.
"This is an extremely sad day for the Corps of Royal Engineers and everyone serving with Task Force Helmand. Our thoughts are with the soldier's family and friends at this time.
"The soldier's family have been informed and they have requested a 24-hour period of grace before further details are released."
Nato said the incident is currently under investigation.
A number of soldiers have been killed by uniformed Afghan personnel in recent months. Last year, 61 people were killed in 54 incidents of insider attacks.
The six British soldiers who died in the last six-month tour of duty were killed in this way. The military refers to such attacks as 'green-on-blue', with green representing the Afghan forces and blue for Nato.
Most recently, an American civilian adviser was shot dead by a female member of the Afghan police on 24 December. An investigation has suggested that the woman was mentally unstable.
Since operations began in Afghanistan in 2001, 439 UK service members have been killed there.