PERTH, Australia (AP) -- Australia's prime minister says officials have narrowed the search zone for the missing Malaysian jetliner. And he says they are "very confident" that the underwater signals they have heard are from the plane's black box recorders.
But Tony Abbott says those electronic signals are fading.
He spoke during a visit to China, where he briefed President Xi Jinping on the search for Flight 370, which vanished five weeks ago on a flight from Malaysia to Beijing.
Search crews are racing against time because the batteries powering the recorders' locator beacons last only about a month. It will be hard to find the devices after the batteries fail, because the water in the area is 15,000 feet deep.
Abbott told the Chinese leader that the next steps in the search will be a "very long, slow and painstaking process."
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