Two more victims were found in the rubble of a partially collapsed apartment building in Florida on Friday, bringing the death count from last week's tragedy to 22, with 126 people still unaccounted for, officials said Friday.

The rise in number of victims came as Miami-Dade County Mayor Daniella Levine Cava said she had signed an order authorizing the demolition of the part of the building that still stands, citing safety issues.

"Our top priority remains search and rescue. I want to be very clear about that," she said.

"We're still evaluating all possible impacts and determining the best timeline to actually begin the demolition."

Emergency personnel had been forced to pause their search and rescue efforts for much of the day Thursday due to concerns about the safety of the pile of debris in Surfside near Miami Beach, but were able to resume work late in the day.

On Thursday night, rescuers recovered the bodies of two victims, including the seven-year-old daughter of a Miami firefighter, Levine Cava said.

The mayor said that while each night had been difficult for rescuers since part of the Champlain Towers South complex collapsed in the early hours of June 24, it had been "uniquely different and more difficult" when the young victim was found.

She said Friday the number of people unaccounted for had dropped to 126, suggesting some people had been located away from the scene. A total of 188 people have now been accounted for.

Officials are keeping an eye on Hurricane Elsa, currently churning in the Caribbean, amid fears the storm could affect the search if it brushes past Florida early next week.

US President Joe Biden visited Florida on Thursday to meet with survivors, relatives of those missing and first responders.