A rescue service veteran on Friday urged the Surfside, Florida community not to lose hope as rescuers desperately search for survivors after the collapse of a 12-story oceanfront condominium tower.

“You’d be surprised how many people can survive, and that’s the case here. So let’s not lose hope, “Carlos Castillo, who helped develop the Urban Search and Rescue Response System for the United States, told CNBC” The News with Shepard Smith. “

“I had a personal experience. The first time I replied was an earthquake in what was then Soviet Armenia. We rescued a 60-year-old woman who was trapped for five days and she survived,” said Castillo. the chief development officer of the emergency management company Tidal Group.

159 people were still missing as of Friday evening, at least four people were confirmed dead. Rescuers use jackhammers, picks, sledge hammers, shovels, and their own hands to dig through the wreckage. They use different types of detection dogs – including some that can sniff out bodies and others that are trained to smell people who are still alive. Rescue workers also brought heavy machinery to pick up huge chunks of concrete and other debris.

Castillo noted that heavy machinery is only brought into areas where there are no survivors, as there is always a risk of secondary collapse.

“It’s done with surgical precision as they come in with heavy equipment, hauling heavier pieces of debris, but the vast majority is moved by hand by rescuers knowing they need to surgically get to someone who is being pinched by part of a part could be standing structure, “said Castillo, who had a 26-year career in fire and rescue services in Miami-Dade County, Florida.

Miami-Dade County’s Mayor Daniella Levine Cava spoke to host Shepard Smith early Friday afternoon and urged the Surfside community not to lose hope in the search and rescue effort.

“Hopefully we’ll let them know our firefighters have hope. They are motivated to find living people and that drives them forward every day, ”said Levine Cava.

The mayor added that while they are currently focused on the rescue effort, there will be an investigation into the building collapse.

“Of course we want to know what caused this and then how we can prevent something like this from ever happening again,” said Levine Cava.

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