Death toll from Florida building collapse rises to 11

New report shows that a local inspector reassured residents of condo's safety in 2018 despite engineer's warning of structural damage

Search and rescue teams look for survivors in the partially collapsed 12-story Champlain Towers South condo building on Monday. AFP

The death toll from the partial collapse of the 12-storey Champlain Towers South in Surfside, Florida, on Thursday has reached 11, Miami-Dade Mayor Daniella Levine Cava said late 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 remain missing after the collapse.

Nearby Miami Beach cancelled its fireworks show and festival for the July 4 holiday "out of respect for the families and victims affected", the city announced.

Emergency responders from Miami Beach have been sent to help with rescue efforts in Surfside, the Miami Beach government said.

A report from National Public Radio released on Friday stated that a town inspector had reassured residents in 2018 that the Surfside condominium building was in "very good shape" a month after an engineer said that the high-rise had suffered major structural damage that required repair.

The 2018 report prepared by an engineering firm employed by the condominium building found serious concrete deterioration in the underground parking garage as well as major structural damage in the concrete slab beneath the pool deck.

The engineer, Frank Morabito, said that 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, NPR reported.

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 that 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 for 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 on Saturday that roof repairs were under way at the time of the collapse but concrete restoration had not yet 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 on Monday 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'

A makeshift memorial has been set up for the victims of the building collapse near the site of the accident in Surfside, Florida. AFP

Rescue workers were combing through the top of the rubble pile on Monday, both on foot and with a crane, aided by clear skies, though the forecast called for chance thunderstorms.

Miami-Dade Fire Rescue representative Maggie Castro told CNN on Monday morning that 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 to assist in the search. 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, Miami-Dade Mayor Daniella Levine 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 shortly after the collapse.

Among those who have been identified were Luis Andres Bermudez, 26, and his mother Ana Ortiz, 46, whose bodies were recovered on Saturday.

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.