truck at the center of the attack and get it out of here, they'll reopen the west side highway. this after a lengthy investigation with a massive team of crime scene technicians, nypd detectives on scene collecting material, taking pictures, talking to witnesses and asking the public for photos or videos that might aid in the investigation. they're confident this lone attacker killed eight now in custody and that terror was his goal. what they have been trying to determine is why. they're trying to backtrack his trail and see who he's been in contact with, who he is talking to, who else might have had knowledge or helped or inspired him to carry out this attack. >> he appears to have followed from almost exactly to a tee the instructions that isis has put out in its social media channels before with instructions to their followers on how to carry out such an attack.