CNN  — 

At least seven people were killed and several others injured Saturday after part of a ferry dock collapsed on Georgia’s Sapelo Island, according to the Georgia Department of Natural Resources.

It happened as crowds gathered on the island for a celebration of its tiny Gullah-Geechee community of Black slave descendants.

At least 20 people were plunged into the water when a gangway collapsed on the visitor ferry dock shortly before 4 p.m., Georgia DNR Capt. Chris Hodge said at a Saturday night news conference. A McIntosh County commissioner previously said a boat hit the dock but a DNR spokesperson later told The Associated Press there was no collision and it is unclear why the dock collapsed.

Among those who died was a chaplain for the DNR, Georgia DNR spokesperson Melissa Cummings confirmed to CNN.

Six people were critically injured and two people were flown by air ambulance to hospitals for treatment, Hodge said.

“The gangway has been secured on Sapelo Island and the incident is currently under investigation,” the Georgia DNR said in its release.

Multiple agencies responded when part of a ferry dock collapsed on Georgia’s Sapelo Island.

The DNR said multiple other emergency agencies assisted them by deploying boats equipped with side-scan sonar and helicopters for search and rescue missions.

The McIntosh County Sheriff’s Office said earlier Saturday in a Facebook post it was “working an active situation on Sapelo Island,” with multiple agencies. “We have set up a family re-unification point at the Elm Grove Baptist Church,” the post said. “We ask that anyone searching for family members, please check there first.”

CNN has reached out to the McIntosh County Sheriff’s Office, McIntosh County EMS and the US Coast Guard for more information.

Both President Joe Biden and Georgia Gov. Brian Kemp said they were “heartbroken” over the news of the collapse in separate statements on Saturday.

“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,” Biden said.

He added the White House is in touch with state and local officials to provide any and all assistance that would be helpful to the community.

“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.” Kemp said in a post on X.

The City of Darien said the accident turned the community’s day of celebration into tragedy. “Please keep those who lost their lives today, the families of those affected and our community in your prayers,” the city said in a Facebook post.

The Sapelo Island Cultural And Revitalization Society, which hosts the island’s annual Cultural Day Festival, also said it was “heartbroken” and grateful for the support people have shown.

“Our thoughts and prayers are with those who were injured,” the nonprofit organization said in a Facebook post. “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.”

Sapelo Island is a barrier island off the coast of Georgia, accessible only by boat. The island is home to around 70 full-time residents, according to Explore Georgia. Most of them are descended from slaves who worked on plantations.

Ferries typically depart from the Sapelo-side dock three times a day, taking visitors to the mainland dock in Meridian. The island suffered serious damage during Hurricane Helene, including a six-day power outage, according to the Southern Poverty Law Center.

This story has been updated with additional information.