Fire interferes with search for survivors of the Florida condo collapse, officials say

As crews continued to search for survivors of Thursday's partial collapse of a Surfside, Florida, condo building, officials said Saturday that an ongoing fire underneath the rubble has made the rescue effort difficult.

"It's a very deep fire," Miami-Dade County Mayor Daniella Levine Cava told reporters during a Saturday morning news conference. "It's extremely difficult to locate the source of the fire. So they've been working around the clock, these fire rescue teams, these brave men and women, under the rubble to fix this problem so they can get on, but it is hampering our search efforts."

Since the fire started, it has spread laterally throughout the pile, she said.

"Obviously, the smoke itself is the biggest barrier right now to proceeding in those areas. So we created a trench using heavy equipment to try to isolate the fire and continue searching for victims in the part of the pile that we can access," the mayor said. "No further victims have been found."

The death toll stands at four. Eleven others were injured and more than 150 people remain unaccounted for, authorities said Saturday.

President Joe Biden tweeted his condolences to those who have lost loved ones and says his administration stands ready to help with local and state efforts.

"My heart is with the community of Surfside as they grieve their lost loved ones and wait anxiously as search and rescue efforts continue," he tweeted. "Yesterday I spoke with Gov. DeSantis to let him know that we are ready to provide assistance as needed by state and local officials."

Fire Rescue Chief Alan Cominsky said they have been using sonar equipment to detect any possible sound in the rubble but have not "heard sound for a while."

"Again, when we say 'sounds,' it’s not distinct. … It’s just things that we hear so we focus on that area as we’re doing our search," he told reporters. "And no, we haven’t heard anything different in regards to the sounds.”

Meanwhile, officials are considering whether Champlain Towers South's sister property should be temporarily evacuated.

Surfside Mayor Charles Burkett told NBC Miami that he asked Levine Cava and U.S. Sen. Rick Scott, R-Fla., if Champlain Towers North should be vacated in order for a forensic study to be conducted.

Burkett said that he does not believe Champlain Towers North could potentially fall down, but he said he did not have an answer about whether the building is safe, noting that it is the same design as Champlain Towers South and was probably built with the same material.

According to Miami Condo Investments, Champlain Towers North is 12 stories, the same as its sister property, and has 111 condos.

The cause of Thursday's collapse is still under investigation. A 2018 structural report was released Friday night that shows evidence of cracks and damage in the building. According to the report, an engineer warned there was "major structural damage" in the building.

Burkett told NBC Miami that he has not yet received the report and asked for it to be sent to him. He also said he was not aware of its findings.

Levine Cava shared similar sentiments, telling reporters Saturday that she had not known about the report.

In an interview with NBC's "TODAY" show, she said investigators and structural engineers will look into all potential causes of the collapse.

“We have hope, and we need to continue to focus on that,” Levine Cava said. “We are going to get to the bottom of this and find answers and prevent it from ever happening again.”

In the meantime, Miami-Dade County will conduct audits of all buildings 40 years and older, the mayor announced Saturday. The process will be conducted within the next 30 days.

"We want to make sure that every building has completed its recertification process, and we want to move swiftly to remediate any issues that may have been identified in that process," Levine Cava said.

Records showed Champlain Towers South was built in 1981. The building is across from a beach in the oceanfront community of about 6,000 people.

Surfside Commissioner Eliana Salzhauer said Thursday that the building was undergoing inspection for its 40-year recertification, which takes about a year. Champlain Towers North was built around the same time, according to the commissioner.