PERTH - The search for a missing Malaysia Airlines jetliner resumed on Saturday, five weeks after the plane disappeared from radar screens, amid fears that batteries powering signals from the black box recorder on board may have died.
Australian Prime Minister Tony Abbott warned on Friday that signals picked up during the search in the remote southern Indian Ocean, believed to be "pings" from the black box recorders, were fading.
Malaysia Airlines Flight MH370 disappeared soon after taking off on March 8 from Kuala Lumpur bound for Beijing with 227 passengers and 12 crew on board, triggering a multinational search that is now focused on the Indian Ocean.
Search officials say they are confident they know the approximate position of the black box recorder, although they have determined that the latest "ping', picked up by searchers on Thursday, was not from the missing aircraft.
Batteries in the black box recorder are already past their normal 30-day life, making the search to find it on the murky sea bed all the more urgent. Once they are confident they have located it, searchers then plan to deploy a small unmanned"robot" known as an Autonomous Underwater Vehicle. "Work continues in an effort to narrow the underwater search area for when the Autonomous Underwater Vehicle is deployed,"the Australian agency coordinating the search said on Saturday. "There have been no confirmed acoustic detections over the past 24 hours," it said in a statement.
The black box records data from the cockpit and conversations among flight crew and may provide answers about what happened to the plane, which flew thousands of kilometres off course after taking off.
The mystery has sparked the most expensive search and rescue operation in aviation history.
Investigators probing the disappearance suspect that the co-pilot of the jetliner tried to make a call with his cellphone after the plane was diverted from its scheduled route, Malaysia's New Straits Times reported sources as saying on Saturday.
The newspaper cited unidentified investigative sources as saying the attempted call from co-pilot Fariq Abdul Hamid's phone was picked up by a cellphone tower as the plane was about 200 nautical miles northwest of the west coast state of Penang. That was around where military radar made its last sighting of the missing jet at 2:15 a.m. local time on March 8.
Government officials could not immediately be reached for comment on the report. The New Straits Times quoted acting Transport Minister Hishammuddin Hussein as saying that the report needed to be verified.
But he appeared to cast doubt on the report by saying: "If this did happen, we would have known about it earlier." Malaysia is focusing its criminal investigation on the cabin crew and the pilots of the plane - 53-year-old captain Zaharie Ahmad Shah and 27-year old Fariq - after clearing all 227 passengers of any involvement, police have said.
Malaysia's government has also begun investigating civil aviation and military authorities to determine why opportunities to identify and track the flight were missed in the chaotic hours after it vanished.