Peter Moore, a British consultant, was giving an IT lecture to a class of civil servants at a Finance Ministry building in Baghdad a year ago when the nightmare started.

Gunmen wearing police uniforms stormed the classroom and seized Mr Moore as well as two British guards who had been protecting him. A second consultant concealed among a group of Iraqis escaped detection.

The 40-strong gang overpowered two other British guards who had been waiting outside the building, then bundled their haul into a line of waiting vehicles and sped off.

It was one of the most brazen abductions of Westerners in Iraq since the fall of Saddam Hussein. There was an emergency response meeting in Whitehall, and hostage rescue experts were sent to the British Embassy in Baghdad to bolster a team that was already trying to gather intelligence, while commandos staged raids on suspected insurgent hideouts.

In the immediate aftermath, no one claimed responsibility, no ransom demand was made and no word was heard from the hostages.

Just over a week after the abduction, Dominic Asquith, then Britain’s Ambassador to Iraq, made the first formal appeal for the hostages’ release, indicating that the Government was prepared to talk to the kidnappers.

Such appeals have been few and far between. Instead, the Foreign and Commonwealth Office adopted a policy of silence. It urged the media to refrain from revealing personal details about the Britons, in the belief that keeping their profile low would increase their chances of release. When General David Petraeus, commander of US forces in Iraq, told The Times last June that a group funded, trained and armed by Tehran was responsible — and that his men had narrowly missed freeing the hostages — it prompted anger in the Foreign Office.

There had been speculation that the abductors were Shia Muslim militants backed by Iran, where the Britons are now reportedly being held. General Petraeus identified the group as a secret cell of al-Mahdi Army, a Shia militia loyal to Moqtada al-Sadr.

Away from the official rescue effort, a charismatic British vicar who works in Baghdad decided to get involved. Canon Andrew White has experience of hostage negotiations and also knew the four kidnapped security guards.

“I started searching for them on May 29, the day that they were taken,” said Canon White, who is dubbed the Vicar of Baghdad. “The first thing I did was phone various religious leaders in Baghdad and then I went to see someone.”

Canon White said that he had devoted vast amounts of resources and time trying to track the men down. “I have not taken one holiday,” said the vicar, 42, who splits his time between Baghdad and England, where he has a wife and two young sons.

Afflicted with multiple sclerosis, which forces him to walk with a cane to keep his balance, Canon White said the past 12 months had been dotted with disappointments. “So many times we have thought we were nearly there and we have not been . . . But you cannot give up.” His efforts appear to be treated with scepticism by the Foreign Office, however.

Other parties that have been following developments closely include Guardrail, the Canadian security company that employed the four guards, and BearingPoint, Mr Moore’s employer, a US management consultancy.

In a breakthrough last December, the kidnappers spoke out for the first time, releasing video footage of one of the hostages, who said that his name was Jason. The kidnappers said that a hostage would be killed if British troops did not leave Iraq in ten days.

In an exchange conducted through the media, Gordon Brown demanded the release of the five men. The only other hostage to be shown publicly on television was Mr Moore. In February the kidnappers released a video of him dressed in a tracksuit, appealing to Mr Brown to secure his release by freeing nine Iraqi prisoners.

As the anniversary of the kidnapping looms, Mr White says that he believes the men are well, adding: “We are working flat out every day for them.”

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