Article published on the 2008-09-26 Latest update 2008-09-26 11:18 TU
Police say the suspects had left suicide notes in their apartments saying that they were ready to die in "holy war" and that they had been watched by police for several months.
A KLM spokesperson said the passengers were asked to get off the plane; a baggage inspection and cabin check took place. The airplane, bound for Amsterdam, continued on to its destination an hour later.
The incident does not appear to be linked to the announcement by Germany's Federal Crime Office on Thursday of an open search for two suspected Islamic terrorists, German Eric Breiniger and Lebanese-born Houssain Al Malla, who the office believes have returned to Germany from Pakistan. Posters have been put up with photos of the two men.
Germany, which has 3,300 troops in Afghanistan under Nato command, has reinforced security and surveillance in response to the threat of attacks by Islamists.
In July 2006 suitcases containing home-made bombs were put on two trains running through Cologne's main train station. They failed to detonate.