are not final. six to eight teams are actively searching for survivors with hundreds on stand by. engineers are also on hand closely monitoring everything to make sure the remaining half of the condo is not in danger of falling. crews dealt with fires at the sight over the weekend. meanwhile, families of those still missing are waiting for any sign of hope. buses brought groups of relatives to the building so they could witness the rescuers at work. a makeshift memorial with pictures of the missing is on a fence feet from where crews are working. as to what caused the collapse, according to the new york times experts who have examined footage of the disaster are focussing on a spot in the lowest part of the condo complex, possibly in or below the underground parking garage where an initial failure could