Debris, smoke at Florida condo building collapse

FLORIDA: Officials say a "very deep fire" is hampering rescue efforts at a collapsed oceanfront condominium near Miami, where authorities are racing to recover more victims beneath the rubble.

Miami-Dade Mayor Daniella Levine Cava says rescuers are using infrared technology, water and foam to battle the blaze, whose source is unclear. Smoke has been the biggest barrier.

159 people remain unaccounted for since the collapse on Thursday. At least four were killed.

Authorities also announced Saturday they are beginning an audit of buildings nearing their 40-year review — like the fallen Champlain Towers South — to make sure they're safe.