Transcript for Police in Spain this morning are scrambling to unravel widening terror plot

We're learning more about the suspects who carried out these attacks following the ISIS playbook using a large vehicle to go in a crowded area. Fears that these attacks may be part of a larger plot, Brian. That's right. Good morning. Police in Spain this morning are scrambling to deal with what is clearly a much bigger plot than just the van attack. Now involving the five additional suspected terrorists shot dead overnight wearing fake suicide bomb vests. The question this morning, how many more members of this ISIS sleeper terror cell are still at large and will they attack again before police close in? Details are still sketchy about the second attempted terror attack in cambrils overnight and the connections of the five dead terrorists to those involved in yesterday's van attack in Barcelona. But the existence and the size of the ISIS terror cell has stunned Spanish police. ISIS promotes these types of attacks because they're easy. You can take people who have received no training, who are using items that are easy to acquire and they can still commit mass murder. Reporter: Police this morning are still racing to locate everyone involved in the Barcelona van attack. Officials say the van was rented in the name of this man, 28-year-old Moroccan born driss oukabir but he claimed his license was stolen and police tell ABC news this morning he has now been released with a new focus on his younger brother as a possible driver. The Barcelona attack comes straight out of the ISIS playbook with its followers urged to use any means available to attack innocent civilians. This ISIS fighter was described as an American goading others to attack. Are you capable of staffing him with a knife or running him over with a car? Reporter: Just this may ISIS gave details of the best truck to use in an attack and now there's been almost a dozen such attacks in Europe, nice, France, 86 killed. Berlin, 11 dead and then in London another dozen people killed. And what Spain is dealing with this morning was no lone wolf attack but instead a much more complex operation involving at least eight people who ISIS claims were soldiers of the caliphate, robin. We're seeing across the country and right here the heightened security because of what's we're seeing. Thanks so much. Brian, thank you. The president meanwhile,

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