The death toll from the partial collapse of Champlain Towers South in Surfside, Florida, on Thursday has reached 11, Miami-Dade Mayor Daniella Levine Cava said on Monday.
Rescue crews are working around the clock, sifting through the rubble for signs of life, even as hopes of finding more survivors grow dimmer by the hour.
More than 150 people are missing.
Nearby Miami Beach cancelled its fireworks show and festival for the July 4 holiday "out of respect for the families and victims affected".
Emergency responders from Miami Beach have been sent to help with rescue efforts in Surfside, the Miami Beach government said.
National Public Radio (NPR) said a town inspector had reassured residents in 2018 that the 12-storey Surfside condominium was in "very good shape" a month after an engineer said the high-rise had suffered major structural damage that required repair.
A 2018 report by structural engineering firm Morabito Consultants found serious concrete deterioration in the underground garage, as well as major structural damage in the concrete slab beneath the pool deck.
The company said the deterioration would "expand exponentially" if it was not repaired in the near future.
But Ross Prieto, a Surfside inspector who had reviewed the report, met residents the following month and assured them the building was safe, said the minutes of the meeting first obtained by NPR.
Mr Prieto is no longer employed by Surfside.
Reuters was unable to reach him, but he told The Miami Herald newspaper he did not remember receiving the report.
In an email to the town manager the morning after the 2018 meeting, Mr Prieto said it had gone "very well" and the response from residents was "positive".
The cause of the collapse remains under investigation.
Gregg Schlesinger, a lawyer and former general contractor who specialises in construction-failure cases, said it was clear the deficiencies identified in the 2018 report were the main cause of the disaster.
But Donna DiMaggio Berger, a lawyer who works with the condo association, said the issues were typical of older buildings in the area and did not alarm board members, all of whom lived in the tower with their families.
Mr Morabito's firm was also retained by the building in 2020 to prepare a 40-year repair plan.
Under Florida law, buildings must go through a recertification process after reaching 40 years of age.
Morabito Consultants said roof repairs were under way at the time of the collapse but concrete restoration had not started.
"We are deeply troubled by this building collapse and are working closely with the investigating authorities to understand why the structure failed," the firm said.
Jason Borden, a structural engineer who surveyed the building last year, told CNN any signs of deterioration were typical for buildings in the seaside community and not serious enough to raise red flags.
"What I did see while I was there did not alarm me at all," he said.
'Time is of the essence'
Rescue workers were combing through the top of the rubble pile on Monday, both on foot and with a crane, aided by clear skies, although possible thunderstorms were forecast.
Miami-Dade Fire Rescue representative Maggie Castro told CNN on Monday the effort was still a rescue mission.
"We are still attempting to find void spaces. We know that time is of the essence," she said. "But, as you can imagine, it's going to be less likely that we are going to be finding survivors."
The teams included experts sent by Israel and Mexico. An American flag on top of one crane rippled in the stiff ocean breeze.
Some relatives of those missing have provided DNA samples to officials and family members were permitted to pay a private visit to the site by special arrangement on Sunday, Ms Cava said.
Police released the names of four victims between the ages of 54 and 83 – a couple married for 58 years, a volunteer Little League baseball coach and the mother of a 15-year-old boy who was pulled alive from the rubble.
The bodies of Luis Andres Bermudez, 26, and his mother Ana Ortiz, 46, were also recovered.
Given the scores of those still missing, the disaster may end up being one of the deadliest non-deliberate structural failures in US history.
Ninety-eight people perished when the roof of the Knickerbocker Theatre in Washington, DC, gave way due to the weight of snow during a silent movie screening in January 1922.
Two interior walkways collapsed into the lobby of the Hyatt Regency hotel in Kansas City, Missouri, during a dance party in July 1981, killing 114.