A French military transport plane taxis at the airport in Saint-Denis along the coast near Saint-Andre on the French Indian Ocean island of Réunion after searching for wreckage from Malaysian Airlines Flight MH370, Aug. 7, 2015. Australian officials dismissed claims that a sonar search turned up more debris from the missing plane. Reuters

Reports that sonar images of two box-like shapes on the floor of the Indian Ocean were from the missing Malaysia Airlines Flight 370 were rejected Thursday by Australian authorities. Objects purportedly discovered by the sonar search, which began after debris from the aircraft was discovered last month on the French island of Réunion in the Indian Ocean, were speculated to have come from the wreck of the Boeing 777.

A wing part found July 29 on Réunion that was confirmed by aviation experts to have come from the missing plane sparked a new search for debris as officials looked for clues to determine what caused the crash. The box-like objects were "category 3" sonar finds by a search and recovery ship that were most likely aircraft debris, Malaysia media reports claimed.

"These are old images, discounted months ago," said a spokesman for Australian Transport Minister Warren Truss, according to the Australian Associated Press (AAP). "In fact, they are the least likely to be aircraft debris."

Flight MH370 disappeared March 8, 2014, with 239 people on board en route from Kuala Lumpur, Malaysia, to Beijing, sparking an international search. The Réunion debris was the first confirmed piece of MH370 wreckage.

More than 400 seabed features have been classified as category 3, which designates sonar objects that are unique from their surroundings, but have low probability of helping the search for the plane, according to AAP.

France plans to end its search for more MH370 debris off Réunion next week as the air and sea investigation shifts beyond the initial area surrounding the island, which officials hope will provide clues to the flight's disappearance.

"Coordinated searches will continue until the beginning of next week. The searches so far had yielded no significant element," said an official on Réunion, reported the Sun Daily.