Australian MH370 search chiefs on Friday played down any link between part of a bag discovered on the French island of La Reunion and the doomed flight.
The suitcase was found on Thursday not far from plane wreckage which fuelled speculation it may be from the missing Malaysia Airlines plane, which vanished last year en route from Kuala Lumpur to Beijing with 239 people on board.
But Martin Dolan, head of the Australian Transport Safety Bureau (ATSB) which is leading the hunt for the plane in the remote southern Indian Ocean, said it appeared unlikely to be linked.
"From what we understand so far there’s much less reason to be positive about the suitcase," he told the Australian Broadcasting Corporation.
"There’s no obvious indication it’s been in the water a long time and so on.
"Obviously it has to be examined very carefully and a proper decision made but we don’t have the same level of confidence in that as potential evidence."
Australia’s Transport and Infrastructure Minister Warren Truss, who oversees the ATSB, was equally cautious.
"In regard to the reports on the suitcase, arrangements have been made to retrieve the suitcase from where it was handed in to a local police station on the island and it will be assessed by the investigators," his spokesman said.
"In short though it may just be rubbish and there is no attached marine life to indicate that it has been in the water for any great length of time. But it will be examined."
The ATSB has scoured more than 50,000 square kilometres (19,000 square miles) of the southern Indian Ocean for the plane, but no physical evidence has ever been found.
Authorities are planning to search a total of 120,000 square kilometres.