Fears were growing for Britain’s three remaining hostages in Iraq after the decomposed bodies of two men were identified as their fellow captives Jason Creswell and Jason Swindlehurst.

Officials in London and Baghdad still hope that Peter Moore, a computer consultant, and two security guards known only as Alan and Alec will be released alive. Sources familiar with the case said that there was a concern that all five men, kidnapped more than two years ago, could be dead.

Stepping up the pressure, Gordon Brown urged the kidnappers, who are believed to have links with Iran, to free the captives immediately.

The hostage-takers said last year that one of the men named Jason had committed suicide. The announcement that both Jasons were dead, however, came as a surprise to officials and a blow for the families. It also raises questions about Britain’s ability to tackle kidnap cases. Graeme Moore, Peter Moore’s father, said that the development was evidence of the Government’s failings. “It proves they mishandled it,” he told The Times.

Forensic science experts at the British Embassy in Baghdad were conducting tests before the bodies could be flown home. Efforts were continuing to establish a cause of death but the bodies had not been mutilated, a government source said.

The Foreign & Commonwealth Office said it was “highly likely” that they were of Mr Creswell, 39, from Portlethen, Aberdeen, and Mr Swindlehurst, 38, from Skelmersdale, Lancashire. It was unclear how the men, security guards for GardaWorld, a Canadian security company, died. Sources said that their bodies were decomposed, indicating that they could have been dead for several months.

The Foreign Office dismissed any connection between the timing of the release of the bodies and the presidential turmoil in Iran. Asaib al-Haq, the Shia group behind the abduction, is suspected of having Iranian links.

A source in Baghdad said that the kidnappers’ decision to give the dead men to Iraqi officials could have been a “goodwill gesture” in response to the freeing earlier this month of an insurgent connected to the gang.

Mr Brown sent his condolences to the families of the dead men and said that he had contacted Nouri al-Maliki, the Iraqi Prime Minister, about the case. “There is no justification for hostage-taking and I call on those holding them to release them immediately,” he said.

Mr Creswell, Mr Swindlehurst, Alan and Alec had been guarding Mr Moore as he trained Iraqi civil servants at a Finance Ministry building when up to 40 gunmen stormed the compound and abducted them on May 29, 2007.

The kidnappers handed over the remains to the Iraqi authorities, who passed them to British diplomats in Baghdad late on Friday. The move shattered the hopes that surfaced only ten days ago that the kidnappers might be preparing to hand over all their captives, after the release by the US military of Laith al-Khazali.

Sami al-Askari, an Iraqi MP, said: “I suppose it’s bad to allow them to die, but it’s better than nothing to hand over the bodies.”

There was no comment from relatives of the dead men last night. Neighbours said Mr Swindlehurst had a daughter but was not married, Mr Creswell is believed to have a partner and two young children.

A letter written by his daughter Maddi, 7, was released in May. It read: “To daddy, I miss you very much. We all want you to come home. When you come back I will give you the bigist \ huge hug. We will never give up until you come home.”

Kidnap timeline

May 29, 2007 Five Britons, including Peter Moore, an IT consultant, and his four security guards are seized in Baghdad

December 4 Islamic Shia Resistance says that it will kill a hostage if UK fails to quit Iraq within ten days

July 20, 2008 Video passed to The Sunday Times claims a hostage called Jason has killed himself

June 20, 2009 David Miliband says two British bodies have been handed over by Iraqi authorities

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