SURFSIDE, Fla. (NewsNation Now) — An 11th person has been confirmed dead after the disastrous collapse of Champlain Tower South, Miami-Dade County Mayor Daniella Levine Cava confirmed Monday night. She confirmed a 10th victim earlier in the day. 150 people are still missing.

Rescue workers dug feverishly for a fifth day Monday and stressed that they could still find survivors in the rubble of a collapsed Florida condo building, a hope family members clung to even though no one has been pulled out alive since the first day the structure fell.

“We have people waiting and waiting and waiting for news,” Levine Cava said of the families who have come to the area hoping for a miracle. “That is excruciating.”

Miami-Dade Fire Chief Alan Cominsky said the raid was a nuisance but it “didn’t impede” the search teams. “We’re hoping to find that possible larger void space or picket where we could find a survivor.”

The chief insists spirits among the search teams are optimistic, but Sinead Imbaro, who joined the effort this week, told NewsNation it’s a difficult job.

“[Cameras] can capture how it looks,” she said. “You can capture how we work. But you cannot capture the emotion that we’re experiencing, or the emotions or the energy around us.”

Families of the missing rode buses to a site nearby from which they could watch teams at work Sunday: firefighters, sniffer dogs and search experts employing radar and sonar devices.

Some families had hoped their visit to the site near the 12-story building would allow them to shout messages to loved ones possibly buried deep inside the pile. As they returned to a nearby hotel, several paused to embrace as they got off the bus. Others walked slowly with arms around each other back to the hotel entrance.

“We are just waiting for answers. That’s what we want,” said Dianne Ohayon, whose parents, Myriam and Arnie Notkin, were in the building. “It’s hard to go through these long days and we haven’t gotten any answers yet.”

The building collapsed just days before a deadline for condo owners to start making steep payments toward more than $9 million in repairs that had been recommended nearly three years earlier, in a report that warned of “major structural damage.”

Authorities Sunday identified the additional four people that had been recovered as Leon Oliwkowicz, 80; Christina Beatriz Elvira, 74; Ana Ortiz, 46; and Luis Bermudez, 26. The number of people left unaccounted for was 152, said Levine Cava. The tenth person announced on Monday has not been identified.The last live person rescued was on Thursday, just hours after the collapse.

Miami-Dade Assistant Fire Chief Raide Jadallah explained that conditions at the site — the building pancaked when it fell — have frustrated crews looking for survivors. Alan Cominsky, chief of the Miami-Dade Fire Rescue Department, said his team is holding out hope of finding someone alive, but must continue to move slowly and methodically.

“The debris field is scattered throughout, and it’s compact, extremely compact,” he said, noting that teams must stabilize and shore up debris as they go.

Levine Cava said six to eight teams are actively searching the pile at any given time, with hundreds of team members on standby ready to rotate in. She said teams have worked around the clock since Thursday, and there was no lack of personnel.

President Joe Biden said in a statement he spoke with FEMA Administrator Deanne Criswell about efforts on the ground after Criswell visited the site. Biden said his administration is prepared to provide assistance and support.

“This is an unimaginably difficult time for the families enduring this tragedy,” Biden said. “My heart goes out to every single person suffering during this awful moment.”

Earl Tilton, who runs a search-and-rescue consulting firm in North Carolina, said rushing into the rubble without careful planning and execution would injure or kill rescuers and the people they are trying to save.

“Moving the wrong piece of debris at the wrong time could cause it to fall” on workers and crush them, he said.

But Tilton agreed families were not wrong to continue holding out hope. During past urban rescues, he said, rescuers have found survivors as long as a week past the initial catastrophe.