LIVE UPDATES: Miami building collapse death toll rises to 4; at least 159 people still missing

Miami first responders and assisting agencies were still conducting a search and rescue operation at the site of a collapsed high-rise apartment building in Surfside, Fla., Friday night as a federal team of experts prepared to deploy from Maryland to inspect the site.

A federal probe into the cause will likely be conducted by investigators from the National Institute of Standards and Technology, according to Glenn Corbett, a former member of the Federal Advisory Committee of the National Construction Safety Team and a fire protection engineer at John Jay College of Criminal Justice in New York. Read more.

Search and rescue teams are currently battling weather and small fires as they comb through the massive pile of rubble that resulted from a 12-story beachfront condo's collapse early Thursday morning, leaving at least 159 people still unaccounted for as of Friday evening. 

Families of those who are unaccounted for are not giving up hope -- but they want answers. Read more.

Residents of the Florida condo complex that collapsed Thursday had previously complained of construction noise that may have resulted from heavy work done to try and ensure the building was ready for its 40-year inspection, according to reports.

The Champlain Towers South condo complex was built in 1981 and faced a mandatory inspection this year. Read more.

Fire Chief Alan Cominsky said smoke seen coming up from the rubble is hindering rescue efforts as a fire burns below the pile.

"I'm not able to distinguish what the temperature is...it's just that it's so deeply seated that we can't get the water there," he said.

Miami-Dade Mayor Daniella Levine Cava said structural engineers had arrived at the site to evaluate amid concerns that the portion of the Champlain Towers South building that is still standing could be unsafe.

Miami-Dade Fire Chief Alan Cominsky said rescuers were focusing underneath the rubble for signs of survivors with K-9 and sonar teams and were investigating potential access points from on top of the pile.

Experts have told Fox News that such search efforts indicate officials still have hope of recovering survivors. If crews brought in heavy machinery to begin clearing rubble, that would put potential survivors at risk -- however Cominsky said such equipment was expected to arrive at the scene soon.

Rescuers are looking for so-called void spaces, areas where collapsed segments of building materials could have saved people from being crushed during the fall. To access those areas with cranes requires slow, meticulous work in order to minimize risk to potential survivors.

The county police director, Alfredo Ramirez, said residents should expect traffic disruptions as rescuers continue to work in the area around the collapse site.

"We are still working," Miami-Dade Mayor Daniella Levine Cava said during a news briefing that kicked off just after 8 p.m. ET Friday. "We are working around the clock, and we still have hope."

She said officials were giving the families of unaccounted for persons twice daily briefings to keep them posted on the progress of the effort.

However the numbers of dead, recovered and unaccounted for had not changed from the morning, she said. No one had been found in hours.

Lauren Patrana, a reporter for CBS Miami, tweeted video of her young son's friend handing out candy and soda's to first responders near the Surfside condo collapse site.

The video shows firefighters in heavy gear and carrying mauls thanking the young boy and his mother, who live nearby, for the gesture.

"A small, simple act that really warmed my heart this morning," she wrote.

Miami-Dade Mayor Daniella Levine Cava tweeted out a video of rescue workers searching for survivors at the Champlain Towers South site Friday evening.

"Let me be clear: The men and women of our @MiamiDadeFire team are the best in the world," she tweeted. "They are working around the clock and using every strategy available to find and save as many loved ones as possible. Please keep them in your prayers."

The White House released a readout of a call between President Biden and Florida Gov. Ron DeSantis Friday afternoon.

The president pledged to provide federal resources to survivors and state and local rescue teams. Biden had already approved an emergency declaration at the request of DeSantis following a deadly collapse of a 12-story condo complex just outside of Miami.

The tragedy led to at least four deaths and dozens of people remain unaccounted for.

Search-and-rescue operations continue in Surfside, Fla., following the collapse of the Champlain Tower South condo complex Thursday morning. 

At least 159 people remain unaccounted for, with at least four people dead as a result of the collapse. Crews continue to search for any survivors who may be trapped beneath the wreckage, using an array of techniques and technology to find any hint of a person still alive.

The crews, which include about 130 firefighters, have reported hearing tapping and other noises, but it is not clear if the noises are human-made or simply the sounds of the rubble shifting. 

Read more here.

A spokesperson for the National Institute of Standards and Technology (NIST) told Fox News they will be sending a crew of six engineers and scientists "to collect firsthand information on the Champlain Towers South collapse that will be used to determine if an investigation or study of the building collapse will be conducted."

NIST spokesperson Jennifer Huergo said in an email that the team's work would not interfere with the search and rescue mission and they will not enter the property once it has been deemed safe.

"The NIST experts will work with federal, state and local authorities to identify and preserve materials that might be helpful in understanding why the collapse occurred," she wrote. "If a full investigation or study is conducted, its ultimate goal would be to determine the technical cause of the collapse and, if indicated, to recommend changes to building codes, standards and practices, or other appropriate actions to improve the structural safety of buildings."

The Miami-Dade Medical Examiner's Office identified its first victim of Thursday morning's tragedy as 54-year-old Stacie Fang, local news station WSVN-TV reported. Fang was reportedly taken to an area hospital after being recovered early Thursday, and died of blunt force injures.

A spokesperson for the medical examiner's office did not immediately respond to Fox News' request seeking confirmation.

According to WSVN, Fang had been staying on the tenth floor of the building. Her son was also rescued after the collapse, according to the report.

"There are no words to describe the tragic loss of our beloved Stacie," reads part of a family statement obtained by the news station,

Bethenny Frankel, through her disaster relief charity, BStrong, is quickly organizing and helping the residents who are displaced after Champlain Towers collapsed in Surfside, Fla. 

The former "Real Housewives" star, 50, has partnered with Global Empowerment Mission, a nonprofit, to help victims. 

"Today, in partnership with @globalempowermentmission, BStrong is distributing $500-$1000 each in cash cards directly to displaced residents in need from the tragic collapse of Champlain Towers in Surfside, Florida. We’re also supplying the Shul of Bal Harbour and other local community centers our BStrong Family Necessities Kits for the entire community affected," Frankel wrote on social media.

To read more, click here.

Heavy cranes are removing debris from the pile using large claws, creating a sound of crashing glass and metal as they pick up a haul and dump it to the side. At the same time, firefighters are tunneling from below, using saws and jackhammers, to search for pockets in the rubble, Miami Dade Fire Chief Ray Jadallah said.

Surfside Mayor Charles Burkett said the removal of the debris should make it safer for rescuers to tunnel into pockets where survivors might be trapped.

“Right now we are picking up dangerous pieces that look like they could fall on our search and rescue guys,” he said.

Periodic downpours, as well as strong winds, were adding to the challenges. A fire somewhere deep within the rubble was also a concern. “We’re working around that, it’s not stopping us,” the mayor said.

The Associated Press contributed.

Local affiliate FOX 32 Chicago reported that 21-year-old Ilan Naibryf, a University of Chicago student, and his girlfriend, Deborah Berezdivin, were believed to have been in the building that collapsed early Thursday morning.

The University of Chicago's Dean of Students, Michele Rasmussen, confirmed the news in a statement provided to FOX 32, writing: "The University of Chicago has confirmed that Ilan Naibryf, a rising fourth-year physics and molecular engineering student in the College, is among the individuals missing following the collapse of the Champlain Towers South condominium building in Surfside, Florida on Thursday, June 24."

"We are listening for sounds," Miami-Dade Fire Chief Jadallah said.

When asked about tapping sounds reported to have been picked up by the sonar technology, Jadallah said that it's "not necessarily tapping, it's just sounds ... it could be various things. It could be just steel twisting, it could be debris raining down. But not specifically sounds of tapping or sounds of human voice."

"Every time that we hear a sound, we concentrate in that area. So, we send additional teams, utilizing the devices, utilizing K9, utilizing personnel. As we continue to hear those sounds we concentrate in those areas."

He said they heard such sounds "throughout the night."

"This work is being done at extreme risk to these individuals. Debris is falling on them as they do their work," Mayor Daniella Levine Cava said. "They are proceeding because they are so motivated and they are taking extraordinary risk on the scene every day."

She also said rescuers "have to be pulled off the shift -- that is how motivated they are to continue their efforts."