One dead after float plane crashes at Washington's Whidbey Island

Rescue crews are searching for nine passengers after accident on Sunday

A US Coast Guard helicopter is flown near Whidbey Island, Washington, where a float plane crashed on Sunday. AP

One person was killed when a float plane crashed along the coast of the US state of Washington on Sunday, the US Coast Guard has said.

Rescue crews were searching for nine other people after the plane, which took off from Friday Harbour on San Juan Island near the Canadian border, crashed in Mutiny Bay, west of Whidbey Island, on its way to Renton, a southern suburb of Seattle.

"One deceased individual was recovered by crews on scene," the coast guard said.

"Nine individuals remain unaccounted for and a safety zone has been put into effect to help facilitate search efforts."

No reason was given for the crash.

The coast guard said it received a report of the crash at 3.11pm and sent helicopters and boats to the area.

Local search and rescue officials were also on the scene.

The last signal from the single-engine propeller plane, a 55-year-old de Havilland Canada DHC-3 Otter, was recorded in the area at 3.08pm local time at 30.5 metres, flight tracking website Flightradar24 said.

Initially, the coast guard's Pacific North-West division said on Twitter that eight adults and one child were on board the aircraft.

It later issued an update to say it was searching for 10 passengers.