Four military search planes were dispatched Thursday to determine whether two large objects bobbing in a remote part of the Indian Ocean are debris from the missing Malaysia Airlines flight.
One of the objects spotted by satellite imagery was 24 metres (almost 80 feet) in length and the other was 5 metres (15 feet). There could be other objects in the area, a four-hour flight from Australia's southwestern coast, said John Young, manager of the Australian Maritime Safety Authority's emergency response division.
``This is a lead, it's probably the best lead we have right now,'' Young said. He cautioned that the objects could be seaborne debris along a shipping route where containers can fall off cargo vessels, although the larger object is longer than a container.
Young told a news conference in Canberra, Australia's capital, that planes had been sent to the area about 2,500 kilometres (1,550 miles) southwest of Perth to check on the objects. He said satellite images ``do not always turn out to be related to the search even if they look good, so we will hold our views on that until they are sighted close-up.''
Australian Prime Minister Tony Abbott earlier told Parliament about the debris, and said Orion search aircraft had been dispatched.
Young said visibility was poor and may hamper efforts to find the objects. He said they ``are relatively indistinct on the imagery ... but those who are experts indicate they are credible sightings. The indication to me is of objects that are a reasonable size and probably awash with water, moving up and down over the surface.''
Military planes from Australia, the U.S. and New Zealand have been searching in a region over the southern Indian Ocean that was narrowed down from 600,000 square kilometres (232,000 square miles) to 305,000 square kilometres (117,000 square miles).
Young said the depth of the ocean in the latest area, which is south from where the search had been focused since Monday, is several thousand meters (yards). He said commercial satellites had been redirected in the hope of getting higher resolution images. He did not say when that would happen. The current images are not sharp enough to determine any markings.
The Australian Maritime Safety Authority released two images of the whitish objects floating on or just under the surface. The images were taken March 16, but Australian Air Commodore John McGarry said it took time to analyze them.
``The task of analyzing imagery is quite difficult, it requires drawing down frames and going through frame by frame. The moment this imagery was discovered to reveal a possible object that might indicate a debris field, we have passed the information from defence across to AMSA for their action,'' he said.
The area where the debris was spotted is about halfway between Australia and desolate islands off the Antarctic.
Flight 370 disappeared March 8 on a night flight from Kuala Lumpur to Beijing. Malaysian authorities have not ruled out any possible explanation, but have said the evidence so far suggests the plane was deliberately turned back across Malaysia to the Strait of Malacca, with its communications systems disabled. They are unsure what happened next.
Police are considering the possibility of hijacking, sabotage, terrorism or issues related to the mental health of the pilots or anyone else on board, and have asked for background checks from abroad on all foreign passengers.