Seven people are dead and half a dozen others were critically injured after a gangway that's part of a ferry dock collapsed on Sapelo Island, Georgia, on Saturday.
Georgia's Department of Natural Resources said at least 20 people went into the water when the structure gave way before 4 p.m., prompting a response from the U.S. Coast Guard and state and local agencies.
Seven people died in the incident and six people were critically injured, said Capt. Chris Hodge, region supervisor for the department’s law enforcement division.
Two people were flown to other hospitals for treatment, he said.
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The cause of the collapse is under investigation, Hodge said.
The Coast Guard was still part of an active search for survivors Saturday night, Petty Officer 3rd Class Jamie Emery said.
"This is not in a recovery phase at this time," she said.
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Two Coast Guard air crews, including one attached to a MH-65 helicopter, were deployed, Emery said.
A reunification center set up at Elm Grove Baptist Church in nearby Meridian, the McIntosh County Office of the Sheriff said on Facebook.
The Sepalo Island Cultural and Revitalization Society organized its annual Cultural Day celebration on the island Saturday, calling it "our most celebrated event." It's not clear if celebrants were on the gangway.
"The Sapelo Island community is grateful for the outpouring of love and support, and we ask that you join us in praying for the families of those who were impacted by this tragedy," the society said in a statement Saturday night.
Tyler Jones, a spokesperson for the Department of Natural Resources, said a celebration of Gullah Geechee culture was underway on the island when the collapse took place, the Associated Press reported.
The centuries-old culture has been maintained by descendants of West and Central African slaves along the coast of the Southeastern United States who were able to retain many of their indigenous African traditions.
President Joe Biden said in a statement Saturday night that he would make federal resources available to affected parties, including the Gullah Geechee.
"We are heartbroken to learn about the ferry dock walkway collapse on Georgia’s Sapelo Island," Biden said, speaking on behalf of himself and the first lady. "What should have been a joyous celebration of Gullah-Geechee culture and history instead turned into tragedy and devastation."
U.S. Sen. Raphael Warnock, D-Ga., on social media platform X called the news “a tragic end to a joyous celebration.”
“The heart of every Georgian is with the Gullah Geechee community & the people of Sapelo Island tonight,” he said.
In a statement, Georgia Gov. Brian Kemp said he, his wife and daughters are “heartbroken by today’s tragedy on Sapelo Island.”
“As state and local first responders continue to work this active scene, we ask that all Georgians join us in praying for those lost, for those still in harm’s way, and for their families,” he said.
According to the Department of Natural Resources’ background on the gangway, the associated dock is used by public ferry vessels, the University of Georgia’s research trawler, and some small boats.
Sapelo Island, on the Atlantic Coast, is about 72 miles south of Savannah.
NBC News' Alex Lo contributed.
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