Tuesdays attacks. Mourners are now flocking to a makeshift memorial to pay their respects for the dozens killed, injured and missing. David in the aftermath of the terror attacks in belgium, the u. S. State department saying a number of american still unaccounted for. Adam shapiro joining us from the newsroom with the latest. Adam. Reporter thats right, david. Official number of american missing in the aftermath of the terrorist attack is two people. 12 are injured. They are saying its a mass casualty event. Difficult to provide specific numbers. There are four americans we highlighted as missing. Among them those who remain unaccounted are a brother and sister from new york. The siblings called their family from the airport and their mother heard the explosion and sounds of broken glass just as the phone went dead. New information that authorities in belgium may have missed opportunities to prevent the at cac. Ibrahim el bakraoui one of the dead suicide bombers in the center was depor