Transcript for New information revealed in the Spain terror attacks

Now to Spain and the new information coming out in the terror attacks that killed 14 people including one American. Look at this new surveillance video shows the van ramming into tourists in Barcelona on la rambla. If you look closely you can see a woman pushing a stroller out of the way. Meanwhile, we're learning these attacks actually could have been much worse and ABC's James Longman is on the ground in Barcelona. James. Reporter: Good morning, Dan and Paula. You may be able to hear chanting here now. People remaining die final in the face of those two terror attacks but authorities here are concerned because that attack could have been much bigger and the country's level of alert now at 4. This morning, officials revealing chilling new details from their investigation into the deadly terrorist attacks in Barcelona and cambrils as multiple suspects remain at large. Investigators reporting the attacks were masterminded by a terrorist cell composed of rou roughly a dozen young men plotting a far deadlier attack in this villa outside Barcelona but a premature ex-please from a bomb leading those plans in ruins and one of the members killed. The surviving suspects hastily escaping leaving behind at least 21 gas canisters that can be seen in the rubble. Those, officials believe, were intended for powerful truck bombs. We're not dealing with the lone wolf offender. We are seeing a group of people who came together for a common cause and that's to commit mass murder. Reporter: Five members of the terrorist cell killed by police after ramming a car into a crowd in cambrils leaving one dead. You can see one of those terrorists lunging towards police wielding a knife before being taken down. Earlier that day in Barcelona, a van seen here on surveillance camera plowing down the famous and bustling street of la rambla. Watch as a mother with a stroller barely makes it out of the way. Bodies and debris left strewn across the pave many. At least 13 people were killed including one American. Police tell ABC news that this man, driss oukabir this is the suspected driver. And two people were left dead and is being investigated as possible terrorism. Well, that attack in Finland grows to the number of European cities that have had to deal with these sorts of terrorist attacks. Here in Barcelona, the hunt is on for the remaining members of that terrorist cell as authorities race to catch them before they have a chance to strike again. Dan, Paula. This story is not over, James, thank you very much for your reporting.

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