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The man had completed the first leg of a flight from Liverpool’s John Lennon Airport to East Africa and was aboard the plane ready to take off for the second leg.

Dutch military police acted on a tip-off from British counter-terrorism officials, sources said, but it was unclear why the man had been allowed to leave the UK.

Britain has introduced a new “watch list” system in the wake of the failed attempt to blow up an airliner as it came in to land at Detroit on Christmas Day. But it has two levels, the second of which does not ban flying.

Somalia has become a focus of counter-terrorism operations by MI5.

Jonathan Evans, its director general, said last week that it was “only a matter of time before we see terrorism on our streets” fuelled by links to the Somali terrorist group al-Shabaab, which is aligned with al-Qaeda.

Mr Evans said there was “a significant number of UK residents training in al-Shabaab camps to fight in the insurgency there”.

Somalia showed “many of the characteristics that made Afghanistan so dangerous as a seedbed for terrorism in the period before the fall of the Taliban”.

Dutch prosecutors said they were investigating the arrested man for links to a terrorist organisation but had not found any explosives.

“A British man of Somali origin has been arrested at Schiphol,” a spokesman said. “At this moment, an inquiry is trying to determine whether or not the man belongs to a foreign terrorist organisation.”

The suspect had travelled from Liverpool en route to Entebbe in Uganda on KLM flight 561. The flight was delayed for two hours following the arrest yesterday morning. He was being questioned last night and Dutch police said they hoped to release more information today.

Scotland Yard said it was aware of the arrest but declined to comment further.

Up to 100 Britons from a variety of ethnic backgrounds are thought to have travelled to Somalia in recent years. Some have died fighting for al-Shabaab.

A number of terrorism suspects have been put under control orders preventing them leaving Britain but the system has been watered down after legal challenges.

Al-Shabaab shocked Uganda during the World Cup in July by setting off bombs which killed 74 people watching a football game on television screens in the capital, Kampala.

Schiphol airport has dramatically stepped up security in response to the Christmas Day incident in which Umar Farouq Abdulmutallab, a former student at University College London, tried to blow himself up with a bomb hidden in his underpants as he flew from Amsterdam to Detroit.