Searches have resumed among the ruins of a collapsed apartment building in Florida, hours after the rest of it was demolished with controlled explosives ahead of a severe storm, according to reports.

The death toll from the collapse of the 12-storey Champlain Tower has reached 24, with 121 missing.

An Israeli Occupation rescue team official said the chances of finding survivors were "close to zero."

The teams resumed their operations at the site, according to American media, hours after the remaining part of the building was demolished amid clouds of smoke and dust.

Authorities had halted search efforts because the building's unstable structure posed a threat to the teams, especially before the possible arrival of Tropical Storm Elsa, likely Tuesday.

The imminent arrival of Storm Elsa, which was expected to reach Cuba by mid-Monday before passing near the Florida Keys, forced authorities to speed up the building's demolition date.

Last week, President Joe Pine visited the disaster site and met with bereaved relatives and rescue workers, saluting their resilience and strength.

Massive search and rescue operations have begun since the tower collapsed in the early hours of June 24, but no survivors have been found since.