Nearly 100 people were unaccounted for after a high-rise condo building partially collapsed near Miami Beach early Thursday, leaving at least four people dead and 10 injured, officials said.
Rescuers continued to search through the debris of the 12-story building in Surfside, a town in Florida's Miami-Dade County, for any survivors Friday morning and were not giving up, officials said.
Raide Jadallah, the assistant chief of operations for Miami-Dade Fire Rescue, said that of the building's 136 units, 55 in the northeast corridor collapsed about 1:30 a.m.
Thirty-five people were pulled from the collapsed part of the building, and two people had been pulled out of the rubble as of Thursday afternoon, Jadallah said.
NBC Miami aired video of a boy being pulled out alive and being placed on a stretcher.
There were 102 people accounted for from the building and 99 people unaccounted for, Miami-Dade County Mayor Daniella Levine Cava told reporters late Thursday afternoon.
In an interview Friday with ABC News, the mayor said the death toll had grown from one to four.
"Tragically, I woke up to learn that three bodies had been pulled from the rubble last night," she said. "Devastating news for families waiting for any hope of survival. And of course, we're going to continue to search. Those three people have not been identified at this time. It does bring our count to four of those who've lost their lives in this tragedy."
"Quite a few" people in the building at the time of the collapse, and some were able to make their way to the front of the structure as the back fell, officials said.
Rescuers with sonar equipment were carefully navigating the collapse in hopes of finding more people.
“It is a very slow and methodical process because every time we start breaching parts of the structure, we get debris that falls on us," said Jadallah, adding that a small fire sparked by the moving rubble had to be put out.
Rescuers are keeping their ears open for any sounds, even if not voices.
“We did receive sounds, not necessarily people talking, but sounds … of a possibility of a banging," Jadallah said late Thursday afternoon. "Short of that we haven’t heard any voices coming from the pile.”
Euclides Acevedo, Paraguay’s foreign minister, said in interviews Thursday that members of President Mario Abdo Benítez’s family were among the missing. They were identified as Sophia López Moreira, the sister of first lady Silvana López Moreira, and her husband, Luis Pettengill. Their three children and Lady Luna Villalba, a worker accompanying the family, were also missing, Acevedo said.
Florida Gov. Ron DeSantis visited the site Thursday afternoon.
"The TV doesn’t do it justice," he said. "It is really, really dramatic to see the collapse of a major structure like that."
He said the Red Cross was setting up displaced residents in hotels, adding that finding answers as to why the building collapsed would take time.
Surfside Commissioner Eliana Salzhauer said search-and-rescue operations could "play out for days."
"I mean, could be weeks until we really know who is under the rubble, who survived, who didn't survive," Salzhauer said. "There's a lot of people unaccounted for, lot of families very concerned."
Surfside Mayor Charles Burkett said Thursday afternoon that "they've got resources like you can't believe here."
"We've got the dogs. We've got the equipment. And we're going to do our very best to save as many people in that pile of rubble as we possibly can," he said.
In addition to the fatality, which was confirmed by Miami-Dade Police, at least 10 people were treated for injuries at the scene, Burkett said.
Aventura Hospital and Medical Center said it received three patients, including two listed in critical condition.
In an interview with TODAY, Burkett said: “It’s hard to imagine how this could happen. Buildings just don’t fall down.”
He said that the building had roof work going on, "but you would never expect that to be the issue. I think that this is a catastrophic failure of that building."
Officials have not said what caused the collapse.
"I mean it looks like a bomb went off, but we're pretty sure a bomb didn't go off," Burkett added.
"When the building came down, it pancaked," Burkett said. "So there's just not a lot of voids that they're finding, or seeing from the outside. That's a tragedy."
"There's just feet in between stories," he later added.
Video from the scene showed a large section of the multistory building collapse into a pile of rubble.
"The Miami-Dade Fire Department has been awesome," Burkett said. "They've got in there and they're in there risking their lives. I mean we don't know if the rest of that building's going to come down."
Emergency crews were going from balcony to balcony with a fire ladder on the side of the building that was left standing, looking for people who might be trapped.
Miami-Dade Fire Rescue was on the scene near 88th Street and Collins Avenue with more than 80 fire rescue units involved, the agency said. That included a technical rescue team that is trained in the removal of victims trapped in complex or confined spaces, fire officials said.
Nicholas Balboa said he was walking his dog when he heard the thunderous sound of the collapse. He ran to the scene and saw the boy who was rescued stick his hand through the rubble.
"He was saying 'Can you see me? Can you see me? Please help,'" Balboa said in an interview with MSNBC.
He went over to the trapped boy and flagged police.
"I just told him 'We're here. We're not going to leave you,'" Balboa said. "The police officer that came told us to move back and I basically told him I'm not leaving. You'll have to arrest me first."
"It looked like it took somewhere between half an hour to an hour to get him out of there. He was pinned pretty good," he said. "He said his mother was in there with him. I couldn't hear her. I couldn't see her. So I mean I hope and pray that she's OK."
President Joe Biden spoke with Miami-Dade County Mayor Daniella Levine Cava on Thursday and offered federal assistance and support.
"We have gotten in touch with FEMA and they are ready to go," Biden said Thursday.
"I say to the people of Florida, whatever help you want the federal government to provide, we are waiting. Just ask us and we will be there," Biden said.
DeSantis declared a state of emergency through an executive order Thursday evening.
Records showed the condo complex, Champlain Towers South, was built in 1981. It is across from a beach in the oceanfront community of about 6,000 people.
Salzhauer said the building was undergoing inspection for its 40-year recertification, which takes about a year. A nearby "sister-building," Champlain Towers North, was built around the same time, according to the commissioner.
A version of this story originally appeared on NBCNews.com.