Florida officials have said they have “significant concerns” regarding the structural integrity of another condominium near the Champlain Towers South building, which collapsed almost two weeks ago, killing at least 36 people. Charles Burkett, mayor of Surfside, said Tuesday that a review is being conducted into Champlain Towers North, the fallen 12-story condo tower’s sister complex, which is still standing near the rubble. Burkett told reporters Towers North is “essentially the same building, built by the same developer at the same time, with the same plans, probably with the same materials” as the Towers South building. “And given we do not know why the first building fell down we have significant concerns about that building and the residents in there,” he said. The storm could become a hurricane again before making landfall between Tampa Bay and Big Bend and crossing northern Florida, forecasters said. Officials are working with the Champlain Towers North condominium board to measure the building’s risk of repeating the collapse. “We’re going to do everything we can,” Burkett said, “to look at those structural systems including ground penetrating radar, the columns, the beams, the slabs, and try to get our arms around what may be happening, what did happen.” Still, Burkett says he’s still uneasy about the building’s integrity. “We have some concerns, not just some, but deep concerns about that building especially given that we don’t know what has happened there, but our engineer is actively working on it, as our town official is.” The death toll at Towers South rose to 36 on Tuesday, after eight more victims were discovered. Three children are confirmed to be among the deceased, and 109 people remained unaccounted for. The recovery effort in Surfside, which is not far from Miami, ramped up on Tuesday due to the threat of severe weather, as Tropical Storm Elsa began lashing Florida. While the storm’s current path looks likely to spare much of the southern part of the state, bands of heavy rain were expected in Surfside as Elsa strengthened. In late June, following the collapse, the Miami-Dade county mayor, Daniella Levine Cava, ordered all residential buildings at least 40 years old and five stories high or more to be audited. For Surfside, Burkett said he is currently responding to inquiries from large buildings in the city, and is “advising them that they should do a full structural review of their systems”.