The painstaking search for Malaysia Airlines Flight 370 got a vote of confidence Friday that the effort is headed in the right direction, but officials noted that much work remains.
"We have very much narrowed down the search area, and we are very confident that the signals that we are detecting are from the black box," Australian Prime Minister Tony Abbott said during an official visit to China, where he met with President Xi Jinping.
Abbott was referring to the plane's flight data recorder and the cockpit voice recorder. Locator beacons attached to them are designed to emit high-pitched signals, or pings.
Over the past week, four such pings have been detected by a ping locator towed by the Australian vessel Ocean Shield.