The death toll in the partial collapse of a high-rise apartment building in Florida has climbed by one to five, a local official said Saturday evening.

"Today our search and rescue teams found another body in the rubble and as well, our search has revealed some human remains," Miami-Dade County Mayor Daniella Levine Cava said at a news conference.

With the identification of three previously recovered bodies, "it means that the unaccounted is now gone down to 156, confirmed deaths are now at a total of five," she said.

The search for the missing residents grew increasingly desperate on Saturday evening, as a smoldering fire hampered rescue efforts and officials said they have not located any signs of life in the mountain of debris.

A newly released 2018 report showed that an engineer found evidence of major structural damage beneath the pool deck and "concrete deterioration" in the underground parking garage of the 12-story oceanfront condominium, three years before it collapsed without warning on Thursday as most residents slept.

The Miami-Dade Fire Rescue received a call at around 1:30 a.m. local time about the partial collapse of the Champlain Towers South condominium in the beachside town of Surfside, about six miles (9.6 kilometers) north of Miami Beach.

The condominium, built in 1981, has 136 units, and approximately 55 of them collapsed on the northeast corridor, said Miami-Dade Fire Rescue Assistant Chief Raide Jadallah. The tower was about to undergo extensive repairs for rusted steel and damaged concrete, the New York Times reported, citing local officials.

At least six Paraguayan nationals were among those unaccounted for, including the sister of Paraguay's first lady, the sister's husband and their three children, Paraguay's Ministry of Foreign Affairs said in a statement.

The Miami-Dade Police have assumed control of the investigation. 

(With input from AFP, Reuters)