Tense waiting game at Britain's hijack terminal as the SAS reception committee stands ready

The call came at 8.36 in the evening. Nothing was certain, it was just a possibility, but a hijacked Afghan aircraft had just left Moscow and was heading west. It was thought to be heading for Frankfurt but there was a chance it was coming to Britain. It was best to be prepared.

The call came at 8.36 in the evening. Nothing was certain, it was just a possibility, but a hijacked Afghan aircraft had just left Moscow and was heading west. It was thought to be heading for Frankfurt but there was a chance it was coming to Britain. It was best to be prepared.

The call, made on Sunday by an official at the Home Office, was the first warning for Essex police that they were about to be thrust into the centre of an international hijacking drama.

And it could not have come soon enough - by midnight the Ariana Boeing 727 was entering British air space and requesting permission to land.

Working from the "Gold Command" suite at police headquarters in Chelmsford, David Stevens, Chief Constable of Essex, was putting into operation a well-prepared plan.

Assembling a large force of officers at the airport, he also arranged for his own firearms team to be reinforced by specialist officers from the Metropolitan Force.

According to set procedures, air-traffic controllers persuaded the hijackers to divert the aircraft, circling over London in a stacking position, to Stansted rather than their preferred locations of Heathrow and Gatwick. Stansted is a designated hijack airport where police and the SAS regularly train for such an eventuality. It is preferred by the security services for handling hijackings because it is more remote than Heathrow and Gatwick and handles less traffic.

And so, by the time the aircraft finally landed, just after 2am yesterday morning most of the plan for containing the situation was already in place.

In addition to the extra officers, fire brigade vehicles and ambulances that had been assembled at he airport, Mr Stevens had mobilised special forces Counter Revolutionary Warfare units, and SAS soldiers equipped with Heckler & Koch MP5 sub-machine-guns, body armour and "flash-bangs" - magnesium-based concussion grenades that can paralyse a terrorist for five seconds -

A succession of unmarked vans under police escort were seen speeding up the M11 from London at about 2.30am. One officer, in full combat gear and with the tell-tale lack of headgear, was seen reporting to the airport's police station around 30 minutes later.

It was there that the operation's "Silver Command" was established to handle the local situation on the ground, co-ordinated during the earlier hours of the morning by Charles Clark, Essex's Deputy Chief Constable, who later handed over to John Broughton, the Assistant Chief Constable. It was also there that the police's two trained negotiators established themselves and, at 5am, began the crucial task of talking to the terrorists.

Initial contact was made through the control tower, with conversations in English. It was reported by police that the men had particularly requested to come to Britain.

On board with them was a total of 165 passengers and crew - 122 men, 20 women and 23 children, including the 14 crew. There was one family party of 35 people who had been on their way to a wedding in northern Afghanistan when the aircraft was seized.

Throughout the night the Government were kept in touch via "Cobr" - the Cabinet Office Briefing Room - in which all the relevant departments are updated on developments and liaise with police and the Army. If necessary M15 and M16 can provide information about the background of the kidnappers or likely repercussions.

The decision to give the plane permission to land at Stansted was described as "a formality" because of the Government's obligations under international air treaties, and concern for the passengers.

The Home Secretary, Jack Straw, was briefed in the early hours of Monday morning and he spoke to the Prime Minister, Tony Blair, hours later.

Meanwhile, back at Stansted, the negotiators were discussing the hijackers' immediate requirements in minute detail. This tactic - a matter of routine - establishes a rapport with the hijackers.

By about 7.30am, the first fruits of this tactic were being witnessed. A generator was taken to the aircraft to power its air conditioning system, and tea and soft drinks were also supplied. This is also typical of negotiators' tactics, according to experts. Mike Yardley, a former Army officer who is also a trained psychologist and military historian, has studied many hostage situations. He said: "The most important thing is to establish a dialogue, and they will offer small favours to the hijackers at the same time as establishing who they are talking to and who is in charge."

Professor Paul Rogers, a terrorism expert at the Department for Peace Studies at the University of Bradford, said: "The key aim is to achieve calm, to reassure the hijackers that nothing dramatic is going to happen and persuade them that there is plenty of time to achieve a settlement."

By noon, this strategy was showing some solid success with five hostages being released - two men, a woman and two children believed to be babies aged three months and six months. This concession was followed by the release of a further three hostages, apparently in return for a supply of meals to the Boeing.

A group of released hostages, escorted by plain-clothed police officers, were seen entering a hotel near the airport yesterday where they are believed to have been debriefed about their ordeal then moved to accommodation in Essex.

Away from the airport, diplomatic efforts were also continuing with the Foreign Office setting up a "channel of communication" to the Taliban through the British High Commissioner in Islamabad and the Taliban's representative in New York.

General Rahmatulla Safi, the Taliban regime's representative in Europe and a former special forces commander in Afghanistan, expressed his confidence in the British ability to deal with the situation.

He said: "The hijackers are foolish, because the forces dealing with them are absolutely professional and the most well known in the world."

But the involvement of the SAS would be the last resort for negotiators. Police said that as long as such a trickle effect of releases could be be maintained military intervention would be unnecessary.

Additional reporting: Andrew Mullins, Jason Bennetto, Katherine Butler and Kate Watson-Smyth