Armed police storm passenger jet to arrest two Somali terror suspects who had left suicide notes

The armed Special Action Commandos grabbed a 23-year-old Somalian, and a 24-year-old German born in Somalia, from the KLM aircraft at Cologne without shots being fired.

German authorities are still searching for terror suspects Housain Al Malla (L) and Eric Breininger (R)

German prosecutors said both were suspected members of the Islamic Jihad Union and had tickets to travel on to Pakistan from Amsterdam via Uganda.

Speculation in Germany was that police believed they were going to Pakistan to receive further terrorist training - or possibly orders for attacks on U.S. bases in the country.

However, it was unclear whether they had managed to smuggle explosives aboard Flight KL1804.

Men in black: Germany's SEK police

After they were taken away, they were made to identify their luggage, which was also seized.

Other passengers aboard the plane had to disembark and identify their baggage before they were allowed to re-board.

The plane, a turboprop-powered Fokker 50, eventually took off 40 minutes late.

The Federal Bureau of Criminal Investigations, Germany's main law enforcement body, said the men had been under surveillance 'for many months'.

But it would not reveal why officers chose to arrest them on the plane or whether they believed the men were poised for an imminent attack.

They were named only partially, as Abdirazak B and Omar D.

Eyewitnesses said the commandos who stormed the plane were dressed from head to toe in black and wore face masks. Several surrounded the plane on the tarmac.

Some boarded through the main door, others entered through hatchways at the back opened by flight attendants.

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

They then boarded the aircraft and arrested the two men - who showed no resistance. 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 serve the UK.

Other SEK units are hunting two men linked to a group of terrorist suspects whose alleged plot to blow up American targets in Germany was foiled in 2007.

Houssain Al Malla, 23, and a German called Eric Breininger, 21, who converted to Islam, are believed to have been training at a terrorist camp in Afghanistan.