Florida Gov. Ron DeSantis said at a Thursday press conference that his state is dealing with a "500-year flooding event" in the aftermath of Hurricane Ian.
"We've never seen storm surge of this magnitude," DeSantis told to reporters. "The amount of water that's been rising, and will likely continue to rise today even as the storm is passing, is basically a 500-year flooding event."
The governor said that first responders from local, state and federal levels were continuing to assess the affected areas, particularly near the barrier islands on the southwest coast of Florida.
There, the U.S. Coast Guard and Urban Search and Rescue Teams, as well as 28 helicopters, were performing "active rescue missions," DeSantis said.
#HurricaneOps 🌀#CoastGuard air crews are actively responding to areas that have been impacted by #HurricaneIan as it moves across the state searching for people in distress and assessing storm damages. 🚁#searchandrescue #semperparatus pic.twitter.com/xWPGpl60tF
— U.S. Coast Guard (@USCG) September 29, 2022
"The President told the Governor he is sending his FEMA Administrator to Florida tomorrow to check in on response efforts and see where additional support is needed," Press Sec. Karine Jean-Pierre said on Twitter. "The President and Governor committed to continued close coordination."
Biden later appeared at FEMA headquarters and said Ian "could be the deadliest hurricane in Florida's history."
"The numbers we have are still unclear, but we're hearing early reports of what may be substantial loss of life," he said.
"We know many families are hurting," Biden added. "Many, many, are hurting today."
JUST IN: "This could be the deadliest hurricane in Florida's history,” Pres. Biden says during Hurricane Ian briefing at FEMA headquarters.
“The numbers are still unclear, but we're hearing early reports of what may be substantial loss of life.” https://t.co/eMyznTawEb pic.twitter.com/W3FX6FaFy3
— ABC News Politics (@ABCPolitics) September 29, 2022
In an appearance on Good Morning America Thursday, Lee County Sheriff Carmine Marceno said he feared fatalities could be in the "hundreds," though he added that those numbers were not confirmed.
Later on CNN, Sheriff Marceno said he didn't know "exact numbers" given the "very preliminary" stages of efforts in Lee County to check on residents and rescue people in trouble because of the storm.
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In response to Marceno's earlier comments, DeSantis said: "I think you'll have more clarity about that in the next day or so as they're able to go to those locations and determine whether people need services or are able to be rescued."
Michael Reaves/Getty Ron DeSantis
He continued, "That number put out by Lee is basically an estimate that these people were calling, the water was rising on their home and they may not have ended up getting through."
— David Ovalle (@DavidOvalle305) September 29, 2022
Near Sanibel Island, a causeway crumbled in sections, according to the Tampa Bay Times, and is now only accessible by boat.
DeSantis said the causeway and the Pine Island Bridge are both "impassable," and that they suffered structural damage and will need to be rebuilt.