Rescue workers walk atop the rubble of a 12-story beachfront condo building that partially collapsed in Florida's Miami-Dade County.

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Rescue workers walk atop the rubble of a 12-story beachfront condo building that partially collapsed in Florida's Miami-Dade County. / AP

Updated June 25, 2021 at 1:46 AM ET

Assistance from the Federal Emergency Management Agency is on the way to the site of the collapse of the 12-story residential condo in Surfside, Fla. President Joe Biden early Friday approved federal assistance to aid state and local response efforts.

Ninety-nine people are still unaccounted for since the building split and part of it came crashing down at around 1:30 a.m. Thursday.

County police have confirmed that one person is dead.

Fire and rescue officials said approximately 55 apartment units were destroyed by the collapse inside the Champlain Towers South complex, a 40-year-old building that houses more than 136 units in total.

Authorities said 102 people have been accounted for from the towers.

"Their locations are known and they are safe," Miami-Dade County Mayor Daniella Levine Cava said at a press conference at around 4:30 p.m. ET Thursday.

She said teams would continue searching the site overnight.

Responders shift rescue efforts

Miami-Dade Fire Rescue posted video of searchers in the flooded basement of the structure.

Fire Rescue Asst. Chief Ray Jadallah said rescue workers have shifted efforts from searching from above the rubble to below. He said a parking structure under the building is offering new pathways into the mass of debris.

Since firefighters arrived on the scene at 1:48 a.m. local time, 37 people have been pulled from the structure alive.

Jadallah called it a slow, dangerous and methodical process.

Crews are working with structural engineers to create new pathways into the decimated building using sonar devices and search cameras. Officials said they have heard "sounds" coming from the inside, and what could be banging. But they haven't heard any voices.

The collapse brought scores of first responders racing to the beachfront property.

Miami-Dade County Commissioner Sally Heyman told NPR that just because someone is unaccounted for doesn't mean the person is still in the building — they may have been away from home for any number of reasons, such as work or travel.

Authorities asked that residents who are safe outside the building to submit a Wellness Check Form so crews don't have to search for them.

'It looks like a bomb went off.'

The collapse occurred around 1:30 a.m. Video obtained by local news station WSVN shows the building caving in on itself over a span of just 15 seconds, leaving behind tons of rubble and a massive plume of dust and debris.

"It looks like a bomb went off," Surfside Mayor Charles Burkett told NBC's Today show.

Burkett said rescue workers have brought in dogs to help assist with the search for survivors but "tragically, there haven't been hits for the dogs, and that's a great disappointment."

"Apparently, when the building came down, it pancaked, so there's just not a lot of voids that they're finding or seeing from the outside," the mayor said.

Video and images showed a scene reminiscent of a war zone, with the entire east-side section of the complex nearly entirely obliterated. Empty beds and mangled air conditioning units dangled from the wreckage, as rescuers combed through the rubble below for survivors.

A family escapes through a partially collapsed staircase

Among those who escaped from the building was Albert Aguero, who was on vacation at the Champlain Towers South building with his wife and two teenage children.

"It woke me up," Aguero told NPR member station WLRN. "I felt the entire room shake. [My wife] jumped out of bed to check on the kids. They were OK. We looked out the balcony. It was all a cloud of smoke."

Aguero said the family managed to escape by rushing through a partially collapsed staircase.

Rubble hangs from the partially collapsed building in Surfside, Fla., on Thursday. The multistory apartment block north of Miami Beach partially collapsed early Thursday morning, sparking a major emergency response.

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Rubble hangs from the partially collapsed building in Surfside, Fla., on Thursday. The multistory apartment block north of Miami Beach partially collapsed early Thursday morning, sparking a major emergency response. / AFP via Getty Images

"When we stepped outside of the apartment, I looked to the left, and the roof was completely caved in on the apartment to our left. Looked forward, which is where the elevators are, and it was just the shaft in a hole," he said.

By midmorning, anyone left "in the intact part of the building" had been safely evacuated, Cava, the mayor of Miami-Dade County, told NPR.

"What a terrible tragedy," she said.

Cava said it was too early for investigators to know what caused the building to collapse but said investigators were on the scene alongside engineers and other emergency responders.

Burkett said work had been ongoing on the building's roof, "but you would never expect that to be the issue." The foundation, he said, "somehow was undermined, and the whole thing came down."

Freddy Ramirez, director of the Miami-Dade Police Department, said his department is serving as the lead investigatory agency into the collapse and is working with the city of Surfside. Miami-Dade Fire Rescue is leading the emergency management of the site and has set up a family reunification center roughly half a mile from the building.

Burkett told NBC that 15 families had already gathered at the city's community center and would soon be relocated to hotels.

This is a developing story. Some details reported by the media may later turn out to be wrong. We will focus on reports from police officials and other authorities, credible news outlets and reporters who are at the scene, and we will update as the situation develops.

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