Searchers are "very confident" that signals detected in the hunt for missing flight MH370 are from the plane's black box, Australia's prime minister says.
Tony Abbott told reporters during a visit to China that authorities have "very much narrowed down the search area" in the southern Indian Ocean.
"We are very confident that the signals that we are detecting are from the black box," Mr Abbott said.
"Nevertheless, we're getting into the stage where the signal from what we are very confident is the black box is starting to fade.
"We are hoping to get as much information as we can before the signal finally expires."
Focused search
The search is currently focused on an 18,000 square mile search area after a fifth ping was detected around 1,400 miles off Perth, in western Australia.
The signal was captured on Thursday by an Australian Air Force P-3C Orion surveillance plane, which has been dropping sonar buoys into the ocean.
However, Joint Agency Coordination Centre (JACC) chief Angus Houston says an initial assessment of the latest signal indicates it is not related to an aircraft's black box.
There is now some confusion surrounding the issue, as Mr Abbott was first quoted as saying he was confident the black box had been found, and then later said he was confident signals picked up by search teams were from a black box.
Today's search
Twelve military aircraft, three civil planes and 13 ships have joined the search today. The Royal Navy vessel HMS Echo is also part of the operation.
Authorities have been racing to locate the plane's data and cockpit recorders, as the ping-emitting beacons are expected to fade.
No floating debris from the Malaysia Airlines aircraft has yet been found, despite the major multinational air and sea operation.
The renewed search operation comes as Malaysia's acting transport minister admitted that mistakes were made in how authorities treated the victims' families.
Hishammuddin Hussein said the missing plane had posed an "unprecedented situation without benchmark".
The Malaysia Airlines plane went missing on March 8 with 239 people on board.
