A court in Germany has convicted four men of being members or of supporting al Qaeda.
The men, in their 20s and 30s, were accused of planning a potentially lethal attack on German soil.
During a two-year trial, prosecuters said the men were acting under direct orders from al Qaeda.
They received jail sentences between four and nine years.
Court spokesman Andrea Vitek said: “According to the court’s findings, preparations for an explosives attack were relatively advanced. A detonator had been built and it was probably only because of police surveillance already in progress that an attack was prevented.”
The group, dubbed the “Dusseldorf cell” by German media was arrested three years ago in the cities of Duesseldorf and Bochum.
German media have reported that a tipoff about the cell came from the US secret services.
Prosecuters said the men planned to detonate a cluster bomb in a crowd of people, followed by a second blast once emergency services arrived to treat the victims.