Trevor Ault has the latest in the New Orleans attack investigation as officials search for possible accomplices after a Texas Army veteran rammed a pickup truck into a crowd celebrating New Year's on Bourbon Street, killing at least 15 and injuring dozens; Pierre Thomas reports as the FBI launches a massive investigation into the background of suspect in the New Orleans attack and if he had any ties to the terrorist group ISIS; Mola Lenghi has details after a Tesla Cybertruck exploded outside the entrance to the Trump International Hotel in Las Vegas, with authorities treating it as a possible act of terrorism; and more on tonight's broadcast of World News Tonight.