DFAT said the pair were citizens of other countries.
Family friend Joseph Waks, another Australian who has been living in Surfside for 12 and a half years, has been supporting the couples large family, some of whom also live in the area.
He said hope was fading that Mr and Mrs Ainsworth, who were renting an apartment on the 11th floor, would be found alive. Authorities have collected DNA from the family members for the process of identifying bodies.
Were just short of 48 hours, so times running against us, he told The Age and Sydney Morning Herald on Saturday morning AEST.
Mr Waks said a makeshift reunification centre has been set up in a nearby hotel to protect the victims families from the midsummer Florida heat.
Ive never seen anything like this before I was standing there yesterday, people were literally coming out with pots and pans and things that they were making to bring to the rescue workers, he said.
While the effort to find survivors has been largely fruitless, a small hand waving through the wreckage soon after the collapse was one rare story of hope.
Nicholas Balboa was walking his dog on the beach when he heard the rumbling he thought was thunder, he said in a telephone interview with the Associated Press. Sensing something was wrong, he dropped off his dog and hurried back outside.
Residents were flooding the streets and pointing at a gaping hole and dust cloud where a seaside condominium tower had collapsed. Fire and rescue crews had not yet arrived, and it was eerily quiet on the back side of the building. As he began to take photos of the wreckage, he heard what sounded like a childs voice.
Balboa, 31, climbed through a pile of glass and rebar in his thongs, desperate to get closer.
Keep yelling so I can follow your voice, Balboa said. He soon saw a hand waving from the rubble.
The boy, Jonah Handler, said he and his mother, Stacie Fang, were the only ones in the apartment that had imploded when part of the building went down. He kept asking about his mother. Balboa and a stranger tried desperately to clear away the rubble surrounding Jonah but it was too heavy. It looked like a wall or support beam, Balboa said.
Stacie Fang, the first confirmed victim of the Miami tower collapse, with her song Joshua, whose rescue was caught on camera. Credit:Facebook
Ill be right back. Im going to get help, Balboa said, trying to comfort the boy.
Please dont leave me, please dont leave me, the boy cried.
He was absolutely terrified. The sheer terror in his voice, that fact that his mother, that he cant find her, said Balboa, who was in town from Arizona visiting his father.
Video of Jonahs rescue has played on repeat in the news, tugging hearts as rescuers with flashlights slowly helped him out from under a pile of cement and twisted steel and carried him away on a stretcher.
Asked about his condition, Lisa Mozloom, a friend of the family said, He will be fine. Hes a miracle. Mozloom said Jonah had been taken to the hospital at one point but said he was stable.
Authorities have said at least four people died in the building collapse, and with 159 still unaccounted for they fear the death toll will rise sharply. They have not publicly released the identities of the deceased, but Mozloom confirmed Fangs death.
There are no words to describe the tragic loss of our beloved Stacie, members of her family said in a statement that Mozloom released on their behalf. They said they were deeply grateful to those who had reached out and that the many heartfelt words of encouragement and love have served as a much needed source of strength during this devastating time.
The family requested privacy on behalf of Stacies son, Jonah, saying they would all need time to to grieve and to try to help each other heal.
Balboa said he was heartbroken to learn of Fangs death.
I lost my mum recently, so I know how its going to be, he said.
with AP
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