Debris found on an Australian island earlier this month is not from missing Malaysia Airlines Flight 370, investigators said Wednesday.

The Australian Transport Safety Bureau was notified on June 9 that the debris had been found on Kangaroo Island off the southern Australian coast.

The bureau, which is running the search in the southern Indian Ocean on Malaysia's behalf, said it had recovered the part but Boeing, the maker of the missing plane, advised that it was "not consistent with the manufacturing specifications of a Boeing commercial aircraft."

The bureau did not say what the debris was likely from.

Flight 370 vanished with 239 people aboard on March 8, 2014, after flying off course during a flight from Kuala Lumpur, Malaysia, to Beijing.

Authorities say the plane likely crashed in the Indian Ocean, but officials have had no luck finding the main underwater wreckage despite an extensive search of a vast area of the ocean off Australia's west coast. Crews are expected to complete their sweep of the 120,000 square kilometer (46,000 square mile) area by August, and there are no plans to extend the hunt beyond that.

Several pieces of the plane have washed up over the past year on coastlines around the Indian Ocean, which is consistent with drifting models based on Flight 370 having crashed in the Indian Ocean.

More debris was found earlier this month washed ashore in Madagascar by a man who previously found a part of Flight 370, but the pieces have yet to be examined by investigators.

Blaine Gibson, an American adventurer who has been hunting for Flight 370 over the past year, said Wednesday that a Malaysian government investigator has twice canceled plans to go to Madagascar to collect the five pieces of potential aircraft debris.

The debris and potential personal effects of passengers found on the same beach are being held by Madagascar authorities.

Malaysian authorities, who are leading the investigation into the plane's disappearance, have procedures in place to examine any suspected debris, though Australia will help analyze Gibson's discovery if asked, the bureau said.

In February, Gibson found debris off the coast of Mozambique that experts later determined came from the missing Boeing 777.