Four search aircraft have been dispatched to the area where the objects were sighted with the first expected to arrive in the area at 6:00 p.m. local time (0700 UTC), John Young, of the Australian Maritime Safety Authority (AMSA), said during a media briefing in Canberra on Thursday.

Young said based on the satellite imagery, "The objects are relatively indistinct. The indication to me is of objects that are of a reasonable size and probably awash with water and bobbing up and down over the surface."

He said the largest was "assessed as being 24 meters (79 feet). There is another one that is smaller than that."

The search area is located 2,500 kilometers (1,553 miles) southwest of Perth and visibility in the area was poor, which would hamper efforts, Young added.

Two ships have also been sent to the area.

"This is a lead, it is probably the best lead we have right now," Young said. "But we need to get there, find them, see them, assess them, to know whether it's really meaningful or not."

Prime Minister Tony Abbott announced the detection of the objects to parliament about an hour before the press conference.

"New and credible information has come to light in relation to the search ... in the south Indian Ocean," Abbott said. "The Australian Maritime Safety Authority (AMSA) has received information based on satellite imagery of objects possibly related to the search."

He also cautioned against drawing premature conclusions.

"We must keep in mind the task of locating these objects will be extremely difficult and it may turn out that they are not related to the search for flight MH370," he said.

Investigators believe the passenger jet was deliberately diverted from its intended route and satellite data suggests the plane could have flown into two vast corridors - on a northern track across Central Asia, or a southern track that would have taken it over the Indian Ocean.

Australia has been searching the southern corridor since Monday.

Flight MH370 and the 239 passengers and crew members on board disappeared on March 8 about an hour after taking off from Kuala Lumpur en route to Beijing.

Flight simulator investigated

Malaysian search authorities have reportedly asked the US Federal Bureau of Investigation (FBI) to help recover data deleted from the flight simulator in the home of the missing plane’s chief pilot, Zaharie Ahmad Shah, a Malaysian police source and US official said Thursday both speaking on condition of anonymity.

Flight simulators are popular among aviation enthusiasts because they recreate the feel of piloting a plane.

Involving the FBI more closely may have also been part of a bid to pacify relatives’ anger at the lack of progress.

Nearly two-thirds of those on board the flight were Chinese, and there were chaotic, emotional scenes Wednesday when several Chinese relatives tried to interrupt Malaysia's daily media briefing at a hotel near Kuala Lumpur airport. The relatives have accused the authorities of withholding information and doing too little to find the plane.

"Top priority"

In his first public comments on the disappearance, US President Barack Obama said Wednesday that finding out what happened to the missing Malaysia Airlines plane was a top US priority.

"We have put every resource that we have available at the disposal of the search process," Obama said in an interview with Dallas-Fort Worth television station KDFW. Three Americans were aboard the flight.

"It's a big piece of planet that we're searching and sometimes these things take time, but we hope and pray that we can get to the bottom of what happened," he said.

hc/jr (Reuters, AFP, AP)