German police commandos grabbed two terrorist suspects from an Amsterdam-bound flight early on Friday before the plane took off from Cologne, police said.
A 23-year-old Somali man and a 24-year-old German born in Somalia were arrested before the KLM flight left the airport, NorthRhine-Westphalia state police said.
A KLM spokeswoman said police boarded the plane when it was at its "point of departure" and grabbed the two suspects.
"Everyone was then forced to leave the plane, and there was a baggage parade to see whose bags belonged to whom", she said.
No further details were immediately available.
Germany's top-selling Bild newspaper, citing police sources, said the two had been under observation for months and a suicide note was found in their apartment saying that they wanted to die for the "jihad" or "holy war.