Bay Area rescue crews take 12-hour shifts in desperate search for condo collapse survivors

Tampa Bay Fire Rescue teams remained in South Florida Friday, working 12-hour shifts to find any survivors and identify missing people from the Surfside condo collapse near Miami.

Challenges are mounting as rescuers shift through the rubble with Hurricane Elsa approaching. A rescue specialist said they have a new perimeter to search now, and they’re not giving up hope for survivors. 

"We’re constantly hopeful. That’s one of our main missions is rescue. We’re still looking forward to making that save, but we are providing some closure to some of the families," said Steven Lawrence, a search and rescue specialist with Florida Task Force 3 from St. Pete Fire Rescue.

Rescue crews are balancing their safety and that of any survivors. 

UPDATES: 4 more victims recovered in rubble, including 7-year-old daughter of Miami firefighter

"We’re always concerned because there’s parts of the building that are still standing, and we’re digging through debris that has already collapsed," said Lawrence.

Those concerns already caused search efforts to temporarily pause Thursday. Crews noticed widening cracks in the remaining part of the building. It’s cleared for now, but structural engineering experts like University of Central Florida’s Dr. Necati Catbas said every move counts.

(Hillsborough Fire Rescue)

"All these pieces that are stacked on each other can shift and people who are surviving in those tight pockets can be exposed to danger," said Dr. Necati Catbas, a civil engineering professor at the University of Central Florida.

RELATED: North Miami Beach orders evacuation of condo building deemed unsafe

Another danger is severe weather, and crews already dealt with rain this week.

"If you have winds, they might push these elements to a different configuration. So that’s definitely a possibility," said Catbas.

Hurricane Elsa complicates the situation even more, so rescuers said they’re getting ready.

"It’s a concern. Obviously, with rescue efforts, it’s going to be a concern here in South Florida. But it’s going to be a concern throughout the state," said Lawrence.

Lawrence said there are a lot of moving parts to the operation, and they are working out what teams to send back home and who else to bring in to help.