The fact that rescuers heard banging sounds from beneath the collapsed Champlain Towers South apartment building in us-regions, just outside miami” target=”_blank”>Miami<

“Typically, when victims make noise, it tends to be like a rhythmic sound,” he said. “Like banging a pipe every 10 seconds. It’s not just some noise that would be repeated for some other reason. You would be listening for something that would be human-made, and you would know the difference.”

The search and rescue effort had been underway for nearly 20 hours as Thursday evening. At least one person had been confirmed dead and 99 were unaccounted for – with rescuers saving more than three dozen people, including at least three who were trapped in the debris.

EXPERT EXPLAINS POSSIBLE REASONS BEHIND FALL OF CHAMPLAIN TOWERS

Pickford said he expected it to continue for up to 48 hours.

This aerial photo shows part of the 12-story oceanfront Champlain Towers South Condo that collapsed early Thursday, June 24, 2021 in Surfside, Fla.  

This aerial photo shows part of the 12-story oceanfront Champlain Towers South Condo that collapsed early Thursday, June 24, 2021 in Surfside, Fla.  
(Amy Beth Bennett /South Florida Sun-Sentinel via AP)

“If you think you have people, you’re gonna keep this a rescue operation, and you’re going to see selected debris remove, nothing big, but if we get this slab out of the way, it might open up a tunnel that we could then maybe get to some people,” he said.

Video of the collapse shows two wings of the building give way – seemingly from the bottom up.

Pickford said it could have been from a sinkhole or something unstable underground, but investigators have not yet determined what caused the high rise to fall.

“Buildings like this do not fall in America,” Surfside Mayor Charles Burkett told Fox News’ Tucker Carlson Thursday night. “This is a third-world phenomenon, and it’s shocking.”

Rescue workers look through the rubble where a wing of a 12-story beachfront condo building collapsed, Thursday, June 24, 2021, in the Surfside area of Miami. (AP Photo/Lynne Sladky)

Rescue workers look through the rubble where a wing of a 12-story beachfront condo building collapsed, Thursday, June 24, 2021, in the Surfside area of Miami. (AP Photo/Lynne Sladky)

He said the “disturbing” collapse was reminiscent of the fall of the Twin Towers in New York City following the Sept. 11, 2001 terror attacks.

Pickford also noted the similarity.

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“To me, it seemed like it fell because it was being undermined,” he said. “It all came down in one section, sort of like the Trade Center did, and that was because the floors underneath each section, they got weak.”

“Florida’s prone to sinkholes,” he added. “It seemed like it had that same kind of feel to it, that something underneath was no good.”