Two British soldiers killed in Afghanistan had been involved in a raid to capture four Taleban members.
British troops were involved in a 'detention operation'
The men died after a one-hour gun battle with Taleban fighters in Sangin, in the province of Helmand, the Ministry of Defence said.
A ministry spokesman said they had four Taleban prisoners with them - but two died in the battle and two escaped.
He said it was a "planned detention operation", but declined to say whether the troops were part of the elite SAS.
The troops were on patrol in Sangin overnight on 26 July into 27 July when the attack happened.
A rocket-propelled grenade destroyed a vehicle and a third soldier was seriously hurt, although he life was not in danger.
Air support and a quick reaction force was called in after the British troops had come under fire from "enemy contact", the ministry spokesman said.
"Four individuals were detained during the operation. Two of the four were killed and two escaped," he said.
The two soldiers' deaths brings the number of personnel killed in action to five since November 2001.
A further five personnel have died in Afghanistan either as a result of illness, non-combat injuries or accidents.