Hurricane Ian destroyed a section of the Sanibel Causeway connecting Sanibel Island and Captiva with mainland Florida, preventing all access for ground vehicles.
Meteorologist Bryan Bennett first showed the collapsed section on Twitter, revealing a missing portion of the causeway dozens of feet long. Storm reporters with the Tampa Bay Times also confirmed the damage, saying the missing section comes right before the bridge rises up toward the island.
Republican Florida Gov. Ron DeSantis confirmed the Sanibel Causeway is "not passable" during a Thursday press briefing. He said both the causeway and the nearby Pine Island Bridge will both require a "structural rebuild."
The Sanibel Causeway is a 12-mile stretch of road that rises into a bridge connecting the island with the mainland. The bridge is the only land-access route between the two areas.
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Hurricane Ian's 150 mph winds ravaged infrastructure across southwestern Florida throughout Wednesday night and Thursday morning. The freeway leading to a major bridge in nearby Ft. Meyers was also destroyed, with the road's asphalt buckling on itself.
Roughly 2.5 million people across Florida are without power in the aftermath of the storm.
Lee County Sheriff Carmine Marceno stated that fatalities in his jurisdiction are likely to be in the hundreds Thursday morning. Lee County contains both Ft. Meyers and Cape Coral.
"Unsure of the exact details because we are just starting to scratch the surface on our assessment," he told ABC News.
Hurricane Ian weakened into a tropical storm as it crossed Florida, but it first struck as a powerful category 5 hurricane. It is now headed up the East Coast and is not expected to gain significant strength.
Ian was the fourth-strongest landfalling hurricane to strike Florida since data started being recorded.