Terror threat faced across Europe 'highly complex'
The head of Germany's domestic intelligence agency has said the deadly attacks in Paris and Brussels show the "highly complex" nature of the terrorism threat facing Europe.
Hans-Georg Maassen told a conference in Berlin that extremists returning from combat zones, home-grown fighters and jihadis who have come in with Europe's recent wave of migrants were all involved in the recent attacks, for which Islamic State (IS) has claimed responsibility.
Mr Maassen said intelligence agencies now "need to take into account multiple attack scenarios by multiple cells against different targets and possibly over many days".
To help, he called for better cross-border information exchange, adding: "To counter criminal groups operating across borders, we need the enhanced international cooperation of security agencies."