(SURFSIDE, Fla.) — One week after a 12-story residential building partially collapsed in South Florida’s Miami-Dade County, at least 18 people have been confirmed dead while 145 others remain unaccounted for, officials said.

The massive search and rescue operation, now in its eighth day, was halted for much of Thursday due to structural concerns, as officials worried about the remaining condo building also collapsing. Crews continue to carefully comb through the pancaked pile of debris in hopes of finding survivors. The partial collapse occurred around 1:15 a.m. on June 24 at the Champlain Towers South condominium in the small, beachside town of Surfside, about 6 miles north of Miami Beach. Approximately 55 of the oceanfront complex’s 136 units were destroyed, according to Miami-Dade Fire Rescue Assistant Chief Raide Jadallah.

Among the bodies most recently pulled from the rubble were two children, ages 4 and 10, according to Miami-Dade County Mayor Daniella Levine Cava.

“Any loss of life — especially given the unexpected, unprecedented nature of this event — is a tragedy. But the loss of our children is too great to bear,” Levine Cava said during a press conference in Surfside on Wednesday evening. “We’re now standing united once again with this terrible new revelation that children are the victims as well.”

All the victims recovered so far have died from “blunt force injuries” due to the collapse, Dr. Emma Lew, director of the Miami-Dade County Medical Examiner Department, told ABC News.

Meanwhile, 139 people who were living or staying in the condominium at the time of the disaster have been accounted for and are safe, according to Levine Cava, who stressed that the numbers are “very fluid” and “continue to change.” Officials previously were including the number of deceased among those accounted for but are now separating the figures.

Concerns about remaining structure temporarily halt search and rescue efforts

Search and rescue efforts were paused early Thursday morning due to concerns about the stability of the remaining structure and the potential danger it poses to the crews. Structural engineers were on site monitoring the situation and determining the next steps, according to Levine Cava.

“We’re doing everything that we can to ensure that the safety of our first responders is paramount and to continue our search and rescue operations as soon as it is safe to do so,” she said at a press conference in Surfside on Thursday morning.

By Thursday evening, the search and rescue mission was “back to work full power,” Surfside Mayor Charles Burkett told ABC News. The work resumed shortly before 5 p.m., Levine Cava said.

Miami-Dade Fire Rescue Chief Alan Cominsky told reporters that crews observed a shift of 6 to 12 inches in a large column hanging from the still-standing structure as well as some slight movement in the concrete floor slabs just after 2 a.m. local time, prompting concerns that the rest of the condominium could collapse.

Earlier, police officers on site had told ABC News that rescuers reported hearing cracks and were investigating the stability of the building.

The structure was cleared by crews last week, and all search and rescue resources have since been shifted to focusing on the pile of rubble. But the two sites are side-by-side and the remaining building has posed challenges for the hundreds of first responders trying to locate any survivors or human remains in the wreckage.

One area of the site had to be roped off on Tuesday due to falling debris. Then on Wednesday, officials said crews were no longer entering the remaining structure because it was considered unstable.

“Given our ongoing safety concerns about the integrity of the building, we’re continuing to restrict access to the collapse zone,” Levine Cava said during a press briefing Thursday evening.

Poor weather conditions — from downpours to lightning storms — have also forced the crews to temporarily halt their round-the-clock efforts in recent days.

Engineers are currently planning for the likely demolition of the building amid the search and rescue operation, Levine Cava said Thursday.

“This is a decision that we need to make extremely carefully and methodically as we consider all the possible impacts to the pile of debris and to our search and rescue operation, as well as considerations of how to best manage the demolition in order to safeguard the integrity of the existing debris field,” she said.

Over the past week, crews have cut a vast trench through the pile of rubble to aid in their search as they try to tunnel through the wreckage and listen for sounds. As they work to reach the bottom of the pile, cameras placed inside show voids and air pockets where people could be trapped, according to officials.

Rescuers are using various assets, equipment and technology, including specially trained dogs that are searching for signs of life, underground sonar systems that can detect victims and crane trucks that can remove huge slabs of concrete from the pile. Crews have removed almost 1,400 tons of debris from the site so far, officials said.

Rescuers are each working 12-hour shifts at a time and the conditions on the pile are “tough” as they risk their lives in hopes of saving others amid heat, humidity and rain, according to Cominsky. But “spirits are high” and they are still “hoping for a positive outcome,” he told reporters.

“We’re exhausting every avenue here,” Cominsky said during the press conference on Wednesday morning. “But it’s a very, very dangerous situation and I can’t understate that.”

Some of the first responders are members of the Miami-Dade Fire Rescue’s urban search and rescue team, Florida Task Force-1, which is part of the Federal Emergency Management Agency’s National Urban Search and Rescue Response System and has been deployed to disasters across the country and around the world. Search and rescue teams from Israel and Mexico have also joined the efforts in Surfside.

Col. Golan Vach, head of a unit of the Israel Defense Forces that specializes in search and rescue operations, arrived in Surfside with his team early Sunday and has been on the scene ever since.

“We find every day new spaces, new tunnels that we can penetrate into the site,” Vach told ABC News on Wednesday.

The ongoing operation in Surfside is the largest-ever deployment of task force resources in Florida’s history for a non-hurricane event. But as the Atlantic hurricane season ramps up, officials are monitoring storms in the region in case some resources deployed to Surfside are needed elsewhere, according to Florida Gov. Ron DeSantis.

Meanwhile, Mayor Burkett has acknowledged that there have been questions from families about when the efforts will transition from search and rescue to recovery.

“This is going to go on until we get everybody out of there,” Burkett said at the press conference on Wednesday morning.

Although officials have continued to express hope that more people will be found alive, no survivors have been discovered in the rubble of the building since the morning it partially collapsed. Bodies, however, have been uncovered throughout the site, which crews have categorized into grids, Cominsky said.

Officials have asked families of the missing to provide DNA samples and unique characteristics of their loved ones, such as tattoos and scars, to help identify those found in the wreckage. Detectives are also in the process of conducting an audit of the list of those accounted and unaccounted for, according to Levine Cava.

Shortly after the building partially collapsed, first responders heard cries for help from a woman trapped in a lower level that was now inside the parking garage. But a wall of concrete and other debris stood in their way, one rescue worker who asked to remain anonymous told Miami ABC affiliate WPLG.

“The first thing I remember is thumping on the wall,” the rescuer recalled. “And then I remember her just talking, ‘I’m here, get me out! Get me out!"”

“We were continuously talking to her,” he added. “‘Honey, we got you. We’re going to get to you."”

Crews never abandoned their effort to reach the woman but the rescue worker said he later learned that she did not survive.

Cominsky confirmed the report during the press conference on Thursday morning, saying crews are “trying to do the best we can” but that “unfortunately we didn’t have success with that.”

Biden meets with officials, rescuers, families in Surfside

President Joe Biden and first lady Jill Biden traveled to Surfside on Thursday to tour the scene of the disaster and meet with officials, first responders, search and rescue teams, as well as families of the victims.

“I just want you to know that we understand,” President Biden told a group of first responders. “What you’re doing now is just hard as hell. Even psychologically. And I just wanted to say thank you. Thank you, thank you, thank you, thank you.”

Addressing reporters Thursday afternoon, Biden said he wanted to send a message to the impacted families that the nation is “here for you.”

“We’ll be in touch with a lot of these families continuing through this process. But there’s much more to be done. We’re ready to do it,” he said.

Prior to his remarks, Biden talked with the families of the victims for nearly three hours.

“I thought it’s important to speak to every single person who wanted to speak to me,” Biden said. “I sat with one woman who had just lost her husband and her little baby boy. Didn’t know what to do. I sat with another family that lost almost an entire family — cousins, brothers, sisters.”

The president said first responders are hopeful they will recover survivors, though acknowledged that the families are “very realistic.”

“They know that the chances are, as each day goes by, diminish slightly. But, at a minimum, they want to recover the bodies,” he said.

Last week, the president approved an emergency declaration in Florida and ordered federal assistance to supplement state and local response efforts in the wake of the partial building collapse.

The Miami-Dade County mayor told reporters that Biden’s visit “will have no impact on what happens at this site.”

“The search and rescue operation will continue as soon as it is safe to do so,” Levine Cava said at the press conference on Thursday morning. “The only reason for this pause is concerns about the standing structure.”

Federal agency that investigated collapse of Twin Towers joins probe
The cause of the partial collapse to a building that has withstood decades of hurricanes remains unknown. The Miami-Dade Police Department is leading an investigation into the incident.

The Miami-Dade County mayor told ABC News last Friday that there was no evidence of foul play so far but that “nothing’s ruled out.”

Miami-Dade State Attorney Katherine Fernandez Rundle said she plans “to request that our Grand Jury look at what steps we can take to safeguard our residents without jeopardizing any scientific, public safety or potential criminal investigations.”

“I know from personally speaking with engineers from the National Institute of Standards and Technology that their investigation to determine exactly how and why the building collapsed will take a long time,” Rundle said in a statement Tuesday. “However, this is a matter of extreme public importance, and as the state attorney elected to keep this community safe, I will not wait.”

Meanwhile, the U.S. Department of Commerce’s National Institute of Standards and Technology has activated its national construction safety team to investigate the partial collapse of the Champlain Towers South. The federal agency investigated the collapse of the so-called Twin Towers in New York City after the terrorist attacks on Sept. 11, 2001.

The probe in Surfside will be a “fact-finding, not fault-finding” and one that could take years, according to the agency’s director, Dr. James Olthoff.

“It will take time, possibly a couple of years, but we will not stop until we have determined the likely cause of this tragedy,” Olthoff said during the press conference in Surfside on Wednesday evening.

What went wrong

Built in the 1980s, the Champlain Towers South was up for its 40-year recertification when it partially collapsed, according to Surfside officials.

The Champlain Towers South Condo Association was preparing to start a new construction project to make updates to the building, which had been through extensive inspections, according to Kenneth Direktor, a lawyer for the association. Direktor told ABC News last Thursday that the construction plans had already been submitted to the town but the only work that had begun was on the roof.

Direktor noted that he hadn’t been warned of any structural issues with the building or about the land it was built on. He said there was water damage to the complex, but that is common for oceanfront properties and wouldn’t have caused the partial collapse.

A 2020 study conducted by Shimon Wdowinski, a professor at Florida International University’s Institute of Environment in Miami, found signs of land subsidence from 1993 to 1999 in the area where the Champlain Towers South condominium is located. But subsidence, or the gradual sinking of land, likely would not on its own cause a building to collapse, according to Wdowinski, who analyzed space-based radar data.

Miami-Dade County officials are aware of the study and are “looking into” it, Levine Cava told ABC News last Friday.

A structural field survey report from October 2018, which was among hundreds of pages of public documents released by the town late Sunday, said the waterproofing below the condominium’s pool deck and entrance drive was failing and causing “major structural damage to the concrete structural slab below these areas.” The New York Times first reported the news.

In a November 2018 email, also released by the town, a Surfside building official, Ross Prieto, told the then-town manager that he had met with the Champlain Towers South residents and “it went very well.”

“The response was very positive from everyone in the room,” Prieto wrote in the email. “All main concerns over their forty year recertification process were addressed. This particular building is not due to begin their forty year until 2021 but they have decided to start the process early which I wholeheartedly endorse and wish that this trend would catch on with other properties.”

A former resident, Susanna Alvarez, told ABC News on Sunday that Prieto said during the 2018 meeting that the condominium was “not in bad shape” — a sentiment that appears to conflict with the structural field survey report penned five weeks earlier.

ABC News obtained a copy of the minutes from the November 2018 meeting of the Champlain Towers South Condo Association, which stated that Prieto had reviewed the structural field survey report and “it appears the building is in very good shape.” NPR was the first to report the news.

Prieto has not responded to ABC News’ repeated requests for comment. He is no longer employed by the town of Surfside. He has been placed on a “leave of absence” from his current post as a building inspector in nearby Doral, according to a statement from the city on Tuesday.

When asked on Monday whether Prieto misled residents during the 2018 meeting, Surfside’s mayor told ABC News: “We’re going to have to find out.”

Meanwhile, Surfside officials and engineers are concerned that recent construction of a nearby residential building may have contributed to instability at the Champlain Towers South and, according to one expert, could have potentially been “the straw that broke the camel’s back.”

“Construction of a neighboring building can certainly impact the conditions, particularly the foundation for an existing building,” Ben Schafer, a structural engineering professor and director of the Ralph S. O’Connor Sustainable Energy Institute at Johns Hopkins University in Baltimore, told ABC News on Tuesday. “A critical flaw or damage must have already existed in the Champlain Towers, but neighboring new construction could be the ‘straw that broke the camel’s back’ in terms of a precipitating event.”

According to media reports from that time, the construction began in 2015 when Terra, a South Florida development firm, started erecting Eighty Seven Park, an 18-story luxury condominium in Miami Beach, across the street from the Champlain Towers South. The project caused such a raucous for residents that Mara Chouela, a board member of the Champlain Towers South Condo Association, reached out to Surfside officials in January 2019, according to records released by the town.

“We are concerned that the construction next to Surfside is too close,” Chouela wrote in an email. “The terra project on Collins and 87 are digging too close to our property and we have concerns regarding the structure of our building. We just wanted to know if any of tour officials could come by and check.”

Chouela received an email back from Prieto, saying: “There is nothing for me to check.”

“The best course of action is to have someone monitor the fence, pool and adjacent areas for damage or hire a consultant to monitor these areas as they are the closest to the construction,” Prieto added.

Residents and board members continued to complain about the project next door for several months, mostly about styrofoam and dirt from the construction site ending up on the Champlain Towers South pool deck and plaza, according to documents released by the town.

A spokesperson for 8701 Collins Development LLC, a joint venture that was established by Terra and other developers involved in the project, told ABC News in a statement Wednesday that they “are confident that the construction of 87 Park did not cause or contribute to the collapse that took place in Surfside on June 24, 2021.”

Another expert, forensic structural engineer Joel Figueroa-Vallines, said that because Eighty Seven Park is “lower in elevation” than the Champlain Towers South, there is a possibility that the construction of the newer building could be cause for concern. But he emphasized that more evidence is still needed.

“It’s almost important and necessary to not discard anything so early on that could potentially be a consideration,” Figueroa-Vallines, founder and president of SEP, an Orlando-based structural engineering firm, told ABC News on Wednesday.

Mehrooz Zamanzadeh, a Pittsburgh-based corrosion engineering expert, told ABC News on Wednesday that any cracks and spalling on the Champlain Towers South should also be examined to determine whether the vibrations from the construction next door played any role in the structural integrity of the condominium.

Regardless, Zamanzadeh said the accelerated deterioration and corrosion of the Champlain Towers South was a critical factor in the partial collapse. He called for mandated corrosion inspections of buildings as well as a recertification process shorter than the town’s current 40-year term.

Jose “Pepe” Diaz, chairman of the Miami-Dade County Commission, told ABC News on Tuesday that he would not speculate what role neighboring construction had on the partial collapse but said officials will investigate it.

Mounting lawsuits in wake of disaster

A slew of lawsuits against the Champlain Towers South Condo Association have already been filed on behalf of survivors and victims, alleging the partial collapse could have been avoided and that the association knew or should have known about the structural damage.

A spokesperson for the Champlain Towers South Condo Association said they cannot comment on pending litigation but that their “focus remains on caring for our friends and neighbors during this difficult time.”

“We continue to work with city, state, and local officials in their search and recovery efforts, and to understand the causes of this tragedy,” the spokesperson told ABC News in a statement Monday. “Our profound thanks go out to all of emergency rescue personnel — professionals and volunteers alike — for their tireless efforts.”

Two law firms, Morgan & Morgan and Saltz Mongeluzzi & Bendesky, announced Wednesday that they have filed an emergency motion — in addition to a lawsuit — requesting site inspection and evidence preservation on behalf of the family of Harry Rosenberg, a resident of the Champlain Towers South who is still missing, along with his daughter and son-in-law.

“The families have no idea whether it is being documented as they peel through that collapse, layer by layer, have no idea what is going to happen to that evidence, and they deserve a voice and a role in this process,” Robert Mongeluzzi, a Philadelphia-based attorney and founder of Saltz Mongeluzzi & Bendesky, said during a press conference in Miami on Wednesday. “We believe that we could give the families a voice and a set of eyes without impairing the critical work of the search and rescue teams that are there, and without affecting at all the investigating agencies that are there.”

Mongeluzzi said the Rosenberg family “do not want this to be about them.”

“They have merely filed this so that we can file this motion on behalf of all the families, all the victims, so that they could start to get answers about why their loved ones are missing,” he added.

ABC News’ Faith Abubey, Judy Block, Lucien Bruggeman, Rachel DeLima, Alexandra Faul, Matt Foster, Stephanie Fuerte, Justin Gomez, Kate Hodgson, T.J. Holmes, Joshua Hoyos, Soorin Kim, Sarah Kolinovsky, Josh Margolin, Victor Oquendo, Dawn Piros, Stephanie Ramos, Laura Romero and Stephanie Wash contributed to this report.

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