The families of five Britons kidnapped in Iraq say they are "deeply upset" to hear two more of the men are likely to have died in captivity.
Government sources told the BBC that security guards Alan McMenemy, from Glasgow, and Alec Maclachlan, from south Wales, were believed dead.
They were kidnapped in 2007 with three others, two of whom have since been shot and their bodies released.
The condition of the fifth man, Peter Moore, from Lincoln, remains unknown.
The Foreign Office says it is still trying to secure the release of all the remaining men.
Business Secretary Lord Mandelson said British officials were doing their "absolute level best" through a variety of channels to bring the hostages to safety.
This is particularly upsetting as the US recently released 5 Iranian prisoners who were responsible for the kidnapping and murder of American soldiers in order to win the release of the British hostages, and once again shows the not surprising complete lack of good faith that the terrorists have been negotiating in.
Our deepest condolences to the families of Mr. Maclachlan and Mr. McMenemy. Please continue to pray for the safety of the remaining hostage, Peter Moore, and for justice to brought to the murderers of these men.
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