Police in Spain have shot dead five men who were wearing fake suicide bomb belts after thirteen people were killed when a man rammed a van into a crowded pedestrian walkway in Barcelona in what looks like a series of coordinated terrorist attacks.
The attacks happened on Thursday.
Director of the Terrorism Research and Analysis Consortium, Jasmine Opperman, says it will be difficult to trace and identify the attacker.
She says what is clear at the moment is that the attack was a directive from someone and that it was a sophisticated attack that went wrong.
Had it gone according to plan, it would have been far more devastating explains Opperman.
Listen to the audio clip below for more on the Spain attacks: