Malaysia has sent a team to the French Indian Ocean island of Reunion to determine whether debris which washed up there is from missing flight MH370.
The Malaysia Airlines Boeing 777 travelling from Kuala Lumpur to Beijing with 239 people on board vanished without trace in March 2014.
Aviation experts have said the debris looks like a wing component from a 777, known as a flaperon.
Malaysia Airlines said it would be "premature" to speculate on its origin.
The two-metre-long (6ft) piece of wreckage washed up on the island, about 600km (370 miles) east of Madagascar, late on Wednesday.
The search efforts for MH370, led by Australia, are focussed on a broad expanse of the southern Indian Ocean - some 6,000km to the east of Reunion, which is a French region.
There have been other plane crashes much closer to Reunion, but flight MH370 is the only Boeing 777 to have disappeared in the area.
An anonymous US official told the Associated Press news agency that, based on the photos, investigators had a "high degree of confidence" that the part was a "flaperon" unique to a Boeing 777 wing.
Aviation expert Xavier Tytelman also said that it presented "incredible similarities" to a Boeing 777 flaperon.
A flaperon is used to both alter the lift characteristics of a wing and control the roll of an aircraft.
French authorities in Reunion are also investigating the debris and Australian investigators are reported to be in touch with manufacturers over the find.
In a statement, Australian Infrastructure Minister Warren Truss said that if the wreckage was identified as being from MH370, this "would be consistent with other analysis and modelling that the resting place of the aircraft is in the southern Indian Ocean".
Any new evidence will be used to refine search efforts, the statement added.
Analysis: BBC's transport correspondent Richard Westcott
Experts should be able to tell fairly quickly if this is a piece of MH370. Aircraft parts have individual serial numbers of them, and the airlines should have records of all those numbers.
So in theory, investigators could check them and give a positive or negative ID. If it is part of the aircraft, it's washed up thousands of miles from where search teams continue to look for debris at the bottom of the sea.
And realistically, although it would confirm the aircraft crashed and broke up, a piece of wing is unlikely to reveal much more about what actually happened on board the plane.
But these are all big "ifs" right now. It could still be yet another false alarm.
Follow Richard: @BBCwestcott
Search teams have been focusing on a 60,000 sq km (23,000 sq mile) area off the coast of Western Australia, where the plane is believed to have crashed.
Flight MH360 vanished after turning away from its north-bound route from Kuala Lumpur.
JUSTCLICK & CONNECT