Transcript for Two people in custody in connection with Barcelona attack

As James mentioned, one terror suspect is dead tonight, two in custody, and there is an urgent manhunt for possible accomplices. One of the men in custody, a 28-year-old accused of renting the van used in that attack. Tonight, did they have help and is this over? ABC's chief investigative correspondent, Brian Ross. Reporter: Police tonight are calling the 28-year old moroccan-born dress oukabir one of three suspected terrorists whose activities they are right now trying to unravel. Authorities say he recently traveled to Morocco, arriving back in Spain just last Sunday, and then rented the van used in the attack. But police say he was not behind the wheel today. Oukabir is now in custody along with a second suspect and authorities say a third man was shot and killed after running a police roadblock. Driss oukabir's Facebook page shows him as a skinny kid at the beach, listening to rap music. And he recently shared this anti-semitic video in praise of the Nazis described as true heroes. The Barcelona attack comes straight out of the ISIS playbook. The terrorist group has urged its followers to carry out similar vehicle attacks, even providing details on the kinds of trucks to use. In nice, France, last year. 86 people killed by a speeding truck on bastille day. In Berlin, 11 were killed in a vehicle attack on the Christmas markets last year, and in London, 1 the people were killed in two separate attacks this year. On the Westminster bridge and then the London bridge. As ISIS suffers more defeats in Iraq and Syria, we can only expect to see more attacks. Reporter: Late today, ISIS took responsibility for the deadly Barcelona attack, calling those involved soldiers of the islamic state. And Brian Ross with us here tonight. Brian reported there were two suspects in custody. One dead, but authorities still believe the driver could be on the loose? Yes. They are looking for at least two more people, and in another twist, the authorities believe the man what rented the van, someone stole his license and he is not involved in any way. He claims a stolen identity. That's right. Thank you.

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