Firefighters, search dogs and emergency crews have spent days scouring rubble for survivors of a residential building that collapsed Thursday morning just north of Miami Beach. The final toll of how many people were killed or injured remains unknown, but it may be one of the deadliest accidental building collapses in American history.
Here’s what we know.
Survivors said they were jolted awake around 1:30 a.m. by fire alarms, falling debris and the feeling of the ground trembling.
Photos from the scene show one side of the 13-story condo tower collapsed, with a giant pile of rubble below. An investigation into the cause has begun, but there are no conclusive answers yet.
How many are unaccounted for?
Mayor Danielle Levine Cava of Miami-Dade County said on Wednesday that as many as 145 people remained missing, nearly a week after the desperate search for survivors began. The authorities have stressed that the numbers will continue to shift as they determine how many people were actually in the building when it collapsed.
Why did the building collapse?
The authorities did not give a reason for the building’s collapse, but an investigation is underway.
Experts who have examined video footage are focusing on a spot in the lowest part of the complex. A single failure could have set off an avalanche of other structural failures, known as “progressive collapse.”
“It does appear to start either at or very near the bottom of the structure,” said Donald O. Dusenberry, a consulting engineer who has investigated many structural collapses. “It’s not like there’s a failure high and it pancaked down.”
The failure could have happened for a variety of reasons, including design flaws or less robust construction allowed under building codes four decades ago.
The building had been about to undergo extensive repairs for rusted steel and damaged concrete, Kenneth S. Direktor, a lawyer involved in the project, said on Thursday. The repairs had been scheduled as part of a review and recertification process for 40-year-old buildings.
Mr. Direktor said that he had seen nothing to suggest that the collapse had anything to do with the issues identified in the engineering review.
In a 2018 report, a consultant found alarming evidence of “major structural damage” to the concrete slab below the pool deck and “abundant” cracking and crumbling of the columns, beams and walls of the parking garage under the building.
What do we know about the building?
The beachside building, Champlain Towers South at 8777 Collins Avenue, was built in 1981.
It was 13 stories tall and had 135 units. At least half of them collapsed.
The area has a robust Jewish community and longtime ties to families from South America. Many Jewish and South American residents were reported to be among the missing.