Rescuers are desperately searching for any survivors trapped in the rubble of a collapsed 12-storey residential building north of Miami.
At least one person has been killed and 99 are still missing, officials say.
As families desperately wait for news, search teams say they are working around the clock and could hear people banging amid the debris.
What caused the 40-year-old building to collapse early Thursday morning remains unclear.
At least 102 people have now been located, but it is uncertain how many were in the building when it came down. Dozens of survivors have been pulled out of the rubble.
As night fell, hundreds of rescuers were using sonar cameras and specially trained dogs as they scoured the rubble for survivors. Teams were tunnelling from an underground car park below the building in an effort to reach victims.
Search and rescue
“Fire and rescue are in there with their search team, with their dogs,” Miami-Dade Police Director Freddy Ramirez told reporters.
“They’re in search-and-rescue mode, and they will be in that mode for a while. They are not quitting. They’re going to work through the night. They are not stopping.” He added.
Search teams detected sounds of banging and other noises, but no voices coming from the tonnes of debris.
But officials say the efforts are dangerous as further rubble could collapse on top of them.
“This process is slow and methodical,” said Ray Jadallah, Miami-Dade Fire Rescue assistant fire chief. “Any time we started breaching parts of the structure, we get rubble falling on us.”
Constant rain and storms are further complicating an already difficult task for the search-and-rescue teams.
Authorities have begun taking DNA samples from relatives of those still missing in case only remains of their family members are found in the rubble.
Relatives of the missing have been huddled around a community centre a few blocks from the collapsed building, waiting for information and fearing the worst.
Nicolas Fernandez said his calls to missing loved ones had gone unanswered.
“I think they’re gone,” he told CBS. “I don’t want to be pessimistic, but we’ve been calling them non-stop with no reply.”