The search for the missing Malaysian Airlines Flight 370 resumed Sunday, as fears mount that batteries powering transmitters from the plane's flight data recorder may have died.
Australian Prime Minister Tony Abbott continues to sound notes of caution, stressing that it may take a long time to locate the Boeing 777 aircraft. Authorities also warn that investigators will have lost their chief means of detection when the flight recorder transmitter batteries lose power. Those batteries are designed to operate for at least 30 days, and many experts speculate they may have already stopped working.
Meanwhile, a leading Malaysian newspaper says investigators probing the plane's disappearance suspect the co-pilot attempted to make a cellphone call after the jetliner deviated from its original course.
The pro-government New Straits Times says investigators believe the call ended abruptly after the phone made contact with a communications tower as the jetliner flew at low altitude about 200 nautical miles northwest the island of Penang. The newspaper said its sources declined to reveal who the caller was trying to reach.
Saturday, Defense Minister Hishammuddin Hussein cast doubt on the report, telling reporters he would have been informed about such a call, if it had indeed taken place.
Pings consistent with a flight data recorder have been detected by an Australian ship using a U.S. naval device to detect black boxes. But no new underwater signals have been heard for several days. If authorities locate more signals, they can then deploy a robot submarine to search the ocean floor.
The Australian prime minister has also cautioned that trying to find anything nearly five kilometers below the surface of the Indian Ocean a thousand kilometers from land is a huge task that will not likely end any time soon.