Terrorists seized on plane

Police said the men had left farewell letters in an apartment in Germany in which they spoke of their "honour" at being able to die in a "holy war".

The armed special action commandos (SEK), who are trained by the SAS, hauled a 23-year-old Somalian and a 24-year-old German born in Somalia off the aircraft without shots being fired. Terrified passengers watched as the drama unfolded on the tarmac.

Witnesses said the commandos were dressed from head to toe in black and wore masks. They carried Heckler and Koch sub-machineguns, gas and stun grenades and Walther sidearms.

Several surrounded the plane, which was bound for Amsterdam. Some boarded the aircraft through the main door, others entered through hatchways at the back opened by flight attendants.

It was unclear whether the suspects, who did not resist arrest, had managed to smuggle explosives aboard the KLM plane Flight KL1804. After they were arrested they were made to identify their hold luggage, which was then seized by police.

Other passengers disembarked and identified their baggage before they were allowed to re-board.

The Federal Bureau of Criminal Investigations, Germany's main law enforcement body, said the men had been under surveillance "for many months" but would not say why they chose to arrest them on the plane today or whether they were poised for an attack.

But the timing, and the dramatic manner of their capture, indicates that police felt time was running out and they had to take the suspects out of circulation swiftly.

KLM said the pilot of the aircraft had received permission to begin his flight and he began taxiing out to the runway when police cut in on an emergency channel and told him to stop.

The SEK are the most highly trained police unit in Germany and used in all anti-terrorist operations. They are under standing orders to shoot to kill suspects if lives are at stake.

Last year they smashed an Islamic cell which had amassed massive quantities of fertilisers to make home-made bombs. The terrorists intended to trigger them across Germany.

In 2000, when a deranged man in Luxembourg took kindergarten children hostage, the local authorities called for the help of the SEK to cross the border and help free them.

The commandos pretended to be a TV crew who granted the man his wish to make a televised statement. As he began to speak the "camera" turned out to be a rifle which fired once, seriously injuring him.

Cologne-Bonn airport - it serves both cities but is nearest to Cologne - is one of Germany's busiest and home to several budget airlines which regularly fly to Britain.