The accident happened around 2 p.m. on Sunday afternoon. The single-engine plane (a Pilatus PC-12) crashed into the sea about 4 miles east of Drum Inlet.
Local authorities initially reported that seven people, including four teenagers, were on the plane. But the Coast Guard confirmed on Monday that eight people were on board. The identities of those killed have not yet been released.
“The plane behaved erratically and then disappeared off the radar,” the US Coast Guard said in a statement.
The search for the occupants is still ongoing. Several helicopters will fly over the area on Monday. The investigation into the cause of the crash is still ongoing.