At least 7 dead, multiple injured after gangway collapses on Georgia's Sapelo Island

At least seven people are dead and several others were critically injured after a gangway collapsed at a landing dock on Sapelo Island off the coast of Georgia, according to state authorities.

At least 20 people went into the water when the gangway collapsed Saturday afternoon, the Georgia Department of Natural Resources said in a statement.

In addition to the seven people who died, six people were critically injured and two others were taken by helicopter to other hospitals for treatment, said Capt. Chris Hodge, with the Georgia Department of Natural Resources, at a news conference Saturday evening.

Authorities received the first 911 call about the gangway collapse at the visitor's landing dock at about 3:50 p.m., Hodge said. The incident sparked a large emergency response, which included local authorities, the Georgia State Patrol and the U.S. Coast Guard. Emergency crews used boats equipped with sonar and helicopters to attempt to find and rescue people who fell into the water.

The cause of the collapse is still under investigation, Hodge said. An engineering and construction team was headed to the scene to examine the collapse site.

The White House released a statement late Saturday from President Joe Biden.

"We are heartbroken to learn about the ferry dock walkway collapse on Georgia’s Sapelo Island," Biden said in the statement. "What should have been a joyous celebration of Gullah-Geechee culture and history instead turned into tragedy and devastation. Jill and I mourn those who lost their lives, and we pray for the injured and anyone still missing. We are also grateful to the first responders at the scene. My team is in touch with state and local officials, and we stand ready to provide any and all assistance that would be helpful to the community."

In a statement posted on X, Georgia Gov. Brian Kemp said he was heartbroken by the tragedy and asked for prayers.

Sapelo Island is located about 70 miles south of Savannah, Georgia.

The dock collapse came the same day residents and visitors were celebrating a community cultural day celebration on the island.

The Georgia Department of National Resources manages Sapelo Island, which is home to a research reserve and the Hog Hammock community, a small enclave made up of a few dozen full-time residents who are the descendants of enslaved African Americans.

The Gullah-Geechee people are descendants of enslaved Africans who were brought to the southeastern U.S., primarily in coastal areas and who, because of their relative isolation, preserved many of their indigenous African traditions.

Vice President Kamala Harris is also "praying for all those who were killed or injured in the collapse of the ferry dock walkway on Georgia’s Sapelo Island," she said in a statement Saturday.

"Our Administration is in close touch with state and local officials, and we have offered any federal support the community might need. As always, we are deeply grateful for the heroism of our first responders," Harris added in the statement.

She added that in the face of this tragedy, they will "continue to celebrate and honor the history, culture, and resilience of the Gullah-Geechee."

ABC News' Michelle Stoddart contributed to this report.