Updated

Florida officials have shifted gears at the Surfside high-rise collapse site from search and rescue to recovery Wednesday – meaning that they don't expect to find additional survivors.

The search for victims of the collapse of a Miami-area high-rise condominium had reached its 14th day, and officials earlier announced they had recovered 18 more bodies from the rubble, bringing the death toll to at least 54, and said 86 people were still unaccounted for. 

The decision to end the rescue effort came after crews completed a search of the last area where they expected to find "voids," or pockets of debris large enough to possibly contain survivors.

Many of the victims found throughout the day were dead in their beds. The high rise crumbled in the early morning hours of June 24, when most residents were sleeping. No survivors have been pulled from the rubble since the hours immediately following the tragedy.

Speaking to families of the victims who remain unaccounted for, Miami-Dade Assistant Fire Chief Raide Jadallah said search teams would stop using rescue dogs and sonar devices meant to find survivors and instead dig through the rubble in search of human remains.

"Our sole responsibility at this point is to bring closure," he told them, according to the Associated Press.

Miami-Dade County Mayor Daniella Levine Cava confirmed the news publicly at a news briefing early Wednesday evening and said the official transition would take place at midnight.

"At this point, we have truly exhausted every option available to us in the search and rescue mission," she said.

The mayor said first responders and members of the public were invited to a vigil to mark the transition and honor the fallen.

"God is still in control, and while there seems to be no chance of finding life in the rubble, a miracle is still possible," Surfside Mayor Charles Burkett added during the briefing, thanking members of the public for their prayers on behalf of the victims.

During another news conference earlier in the day, Cava repeatedly tried not to weep, paused and shook her head as she described the effect of the tragedy on rescue workers and the families of the victims.

"Our commitment to this mission is deeply personal. This is our community, our neighbors, our families. And our first responders have truly searched that pile every single day since the collapse as if they’re searching for their own loved ones," she said.

The latest retrievals reflect what rescue officials have said would be a ramped-up pace of work after the remaining portion of the condo building was demolished Sunday night.

Miami-Dade Assistant Fire Chief Raide Jadallah broke the discovery of the additional bodies and human remains to family members in a private briefing Wednesday morning. The death toll now stands at 46, and officials had already begun to sound more grim about the prospects of finding any surviving victims.

CONDO COLLAPSE: 10 MORE VICTIMS FOUND IN SURFSIDE RUBBLE, MAKING DEATH TOLL 46

Crews "did some significant removal of the pile," Jadallah said. "They were able to get down to various areas to inspect."

Jadallah also reported the somber news that so far no new "voids" have been discovered in the areas that became accessible for the first time after the demolition. Rescuers had hoped to find new pockets where there might be survivors.

14 DAYS AFTER FLORIDA CONDO COLLAPSE, NO SIGNS OF SURVIVORS

An up-close look at the search, in a video released Tuesday by the Miami-Dade County Fire Rescue Department, came as eight more deaths were announced — until Wednesday, the most for a single day since the search began. It also came as rain and wind from Tropical Storm Elsa disrupted the effort.

"Unfortunately, we are not seeing anything positive," county fire chief Alan Cominsky said Tuesday night, referring to workers not finding any open spaces within the mounds of rubble where additional survivors might be found.

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Severe weather from Elsa hindered search efforts to a degree. Lightning forced rescuers to pause their work for two hours early Tuesday, Jadallah said. And winds of 20 mph, with stronger gusts, hampered efforts to move heavy debris with cranes, officials said.

Crews have removed 124 tons of debris from the site, Cominsky said. The debris was being sorted and stored in a warehouse as potential evidence in the investigation into why the building collapsed, officials said.

The Associated Press contributed to this report.