LATEST UPDATE: Investigators probing the disappearance of Malaysia Airlines Flight MH370 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 am local time on March 8.
"The telco's (telecommunications company's) tower established the call that he was trying to make. On why the call was cut off, it was likely because the aircraft was fast moving away from the tower and had not come under the coverage of the next one," the New Straits Times cited a source as saying.
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."
The New Straits Times cited separate investigative sources as saying that a signal had been picked up from Fariq's cellphone, but that it could have resulted from the device being switched on rather than being used to make a call.
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.
Investigators believe that someone with detailed knowledge of both the Boeing 777-200ER and commercial aviation navigation switched off the plane's communications systems before diverting it thousands of miles off its scheduled course.
The search for the missing jetliner in the southern Indian ocean resumed on Saturday, amid fears that batteries powering signals from the black box recorder on board may have died.
Pings rapidly fading
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 were about to die.
Australian Prime Minister Tony Abbott said signals picked up during the search in the remote southern Indian Ocean, believed to be "pings" from the black box recorders, were "rapidly fading".
"While we do have a high degree of confidence that the transmissions that we've been picking up are from flight MH370's black box recorder, no one would underestimate the difficulties of the task still ahead of us," Abbott told a news conference in Beijing.
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 searchers are confident they have located it, they then plan to deploy a small unmanned "robot" known as an Autonomous Underwater Vehicle.
No confirmed acoustic detections
"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.
Narrowing search area
Once the search area is narrowed down to as small as possible "it is our intention to then deploy the submersible, conduct a sonar search of the sea bed and, based on the sonar search, attempt to get a visual of the wreckage," Abbott said.
The US supply ship USNS Cesar Chavez has joined the Australian-led task force to provide logistics support and replenish Australian navy ships, a Pentagon spokesman said.
Up to nine military aircraft, one civilian aircraft and 14 ships were scouring a 41,393 sq km patch of ocean 2,330 km northwest of Perth.
Experts say the process of teasing out the signals from the cacophony of background noise in the sea is slow and exhausting.
An unmanned submarine named Bluefin-21 is on board the Ocean Shield and could be deployed to look for wreckage on the sea floor some 4.5 km (2.8 miles) below the surface once a final search area has been identified.
Australian PM 'very confident' signals are from MH370
Australian Prime Minister Tony Abbott said Friday he was "very confident that signals detected in the search for missing Malaysia Airlines Flight MH370 were from the aircraft's blackbox.
"We have very much narrowed down the search area and we are very confident the signals are from the black box," Abbott said from China, the Australian Broadcasting Corporation reported.
New signal spurs search for missing MH370 black boxes
The logging of a fifth signal spurred Friday's hunt for missing Malaysian airliner MH370 as search crews work round-the-clock to find elusive wreckage in the southern Indian Ocean.
The Australian-led operation out of a Perth airbase is racing to gather as many signals as possible to determine an exact resting place for the Boeing 777 before sending down a submersible to plumb the depths.
The ping-emitting beacons on Flight MH370's data and cockpit voice recorders are expected to fade, more than a month after the plane vanished with 239 people on board.
With analysis of the latest ping underway, the Perth-based Joint Agency Coordination Centre (JACC) said Friday the search area had been further reduced to two zones totalling 46,713 square kilometres (18,06 square miles).
The core of the search is now 2,312 kilometres (1,436 miles) northwest of Perth.
An Australian air force P-3C Orion surveillance plane, which had been dropping dozens of sonar buoys into the remote waters of the search zone, captured the new signal on Thursday afternoon.
"The acoustic data will require further analysis overnight but shows potential of being from a made-made source," JACC chief Angus Houston said in a statement late Thursday.
The Orion was flying close to the area where two signals were detected at the weekend and two more on Tuesday by Australian navy ship Ocean Shield.
The vessel is dragging a US Navy "towed pinger locator" to listen for emissions from the black boxes.
Friday's weather forecast in the search zone was for 10-15 knot southerly winds with isolated showers, seas swells of one to 1.5 metres (three to five feet) and visibility of five kilometres during the showers.
US Seventh fleet spokesman Commander William Marks had earlier voiced optimism that the first two sets of signals showed the hunt was getting "closer and closer".
"When you put those two (sets of pings) together, it makes us very optimistic," Marks told CNN on Thursday.
"This is not something you find with commercial shipping, not something just found in nature -- this is definitely something that is man-made, consistent with what you would find with these black boxes."
Marks said he expected the pings to last "maybe another day or two" as the batteries powering the black box beacons fade after their normal lifespan of about 30 days.
- Still no debris spotted -
No floating debris from the Malaysia Airlines aircraft has yet been found, JACC said, despite the massive multinational air and sea operation.
JACC says the high-tech underwater surveillance is intended to define a reduced and more manageable search area in depths of around four kilometres (2.5 miles).
Houston has stressed the need to find the wreckage and urged repeatedly against unduly inflating hopes, for the sake of the families of missing passengers and crew who have endured a month-long nightmare punctuated by a number of false leads.
But he has voiced renewed optimism as day by day the search edges forward with new information.
No other ships are being allowed to sail near the Ocean Shield as it must work in an environment as free of noise as possible.
But JACC announced that up to 12 military aircraft, three civil aircraft and 13 ships will join Friday's hunt.
JACC says says it should not be long before a US-made autonomous underwater vehicle called a Bluefin-21 will be sent down to investigate, but has cautioned that it will have to operate at the very limits of its capability given the vast depths involved.
In Malaysia, Home Minister Zahid Hamidi said there was "no conclusive evidence yet" from the continuing investigation into what caused the plane to divert from its Kuala Lumpur-Beijing route.
Zahid said 180 people had been interviewed, including relatives of passengers and crew as well as airline ground staff and engineers.
Numerous theories have been put forward to explain MH370's baffling disappearance.
They include a hijacking or terrorist attack, a pilot gone rogue or a sudden catastrophic event that incapacitated the crew and left the plane to fly for hours until it ran out of fuel.
Malaysia Airlines has lost black box data before
Britain's air accidents investigator has criticized Malaysia Airlines for its lack of proper oversight in preserving flight recordings during an incident at London's Heathrow Airport in 2012.
A Boeing 747 bound for Kuala Lumpur, carrying 340 passengers, had to return to Heathrow soon after takeoff because of engine and electrical failures on Aug. 17, 2012. The pilots flew the plane manually and returned to the airport safely.
In a report issued Thursday, Britain's Air Accidents Investigation Branch said all the audio information relating to the incident was lost because the cockpit voice recorder ran on long after the landing. The body said the airline's "procedures for the preservation of flight recordings were not sufficiently robust."
The Heathrow incident was not related to Flight MH370, which went missing last month.
Hunt for MH370 closes in on 'final resting place'
The hunt for more black box "pings" from missing Malaysian airliner MH370 narrowed Thursday to a specific patch of remote ocean after the logging of fresh signals raised hopes wreckage will soon be found.
With dying batteries after more than a month since the Boeing 777 vanished, the head of the Australian-led search Angus Houston wants to pursue the listening operation to help pinpoint the plane's exact location before sending down a submersible.
Houston's Joint Agency Coordination Centre (JACC) announced Thursday the search area off western Australia was now 57,923 square kilometres (22,364 square miles) -- compared to more than 220,000 sq kms previously and 75,000 sq kms on Wednesday.
But Australian ship Ocean Shield is focused on a far smaller area of the Indian Ocean 2,280 kilometres (1,400 miles) northwest of Perth where it picked up two fresh signals Tuesday. They matched a pair of transmissions logged over the weekend.
"When you put those two (sets of pings) together, it makes us very optimistic," US Seventh fleet spokesman commander William Marks said Thursday, adding that the search was getting "closer and closer".
"This is not something you find with commercial shipping, not something just found in nature, this is definitely something that is man-made, consistent with what you would find with these black boxes."
"So we are looking pretty good now."
He told CNN he expected the pings to last "maybe another day or two".
No debris from the aircraft which disappeared on March 8 has yet been found although a large number of objects were spotted on the surface on Wednesday, JACC said.
"But only a small number were able to be recovered. None of the recovered items were believed to be associated with MH370."
Officials had feared that the signals which were initially picked up might not be detected again, particularly since the batteries on the black box tracking beacons have a normal lifespan of about 30 days.
"Yesterday's signals will assist in better defining a reduced and much more manageable search area on the ocean floor," Houston said Wednesday.
"I believe we are searching in the right area but we need to visually identify the aircraft before we can confirm with certainty that this is the final resting place of MH370."
Houston, however, again urged caution for the sake of the families of those aboard the flight which mysteriously vanished en route from Kuala Lumpur to Beijing with 239 people on board, and said the search for more signals would go on.
"Hopefully with lots of transmissions we'll have a tight, small area and... in a matter of days we'll be able to find something on the bottom," he said.
- Clock ticking -
Australia confirmed Wednesday that the fresh signals were consistent with black box recorders, boosting optimism after more than a month of fruitless searching for the missing jetliner.
Searchers are now focusing on tapping transmissions that are expected to be weaker than those signals as the batteries are soon expected to fail.
"With the batteries likely to fade or fail very shortly, we need to get as much positional data as we can so that we can define a very small search area," Houston said.
No other ships will be allowed near the Ocean Shield, as it must work in an environment as free of noise as possible.
With the clock ticking on how long the black boxes batteries, Houston said it would not be long before a US-made autonomous underwater vehicle called a Bluefin 21 would be sent down to investigate.
"I don't think that time is very far away," he said.
He noted that Ocean Shield can search six times the amount of area with a Towed Pinger Locator listening for evidence of the black boxes as can be done with the Bluefin sonar.
Once you put the Bluefin in the water, "there's really no time limit for that", said commander Marks.
Up to 10 military aircraft, four civil planes and 13 ships would take part in the search on Thursday, JACC said.
Fair visibility was predicted for the day with moderate southeasterly winds and isolated showers.
Earlier, experts analysing the first two pulse signals detected by an Australian ship searching for Malaysia Airlines Flight MH370 believe they are consistent with a flight data recorder, search chief Angus Houston said Wednesday.
"They believe the signals to be consistent with the specification and description of a flight data recorder," Houston told reporters.
Australian ship Ocean Shield has detected two more signals in the search for missing Malaysian flight MH370, a senior official said Wednesday.
"Ocean Shield has been able to reacquire the signals on two more occasions, late yesterday afternoon and later last night," said Angus Houston, head of the Joint Agency Coordination Centre.
Australia's MH370 search chief Angus Houston said Wednesday that he believes the Malaysian jet could be found within days -- raising hopes that the agonising wait could soon be over for relatives of the 239 people on board.
Consistent Signals
The hunt for more black box "pings" from missing Malaysian airliner MH370 was narrowing Thursday to a specific patch of remote ocean after two more signals were detected.
The head of the Australian-led search Angus Houston raised hopes Wednesday that wreckage will be found within days even as the black box batteries start to expire.
Houston's Joint Agency Coordination Centre (JACC) announced Thursday the search area off western Australia was now 57,923 square kilometres (22,364 square miles) -- some 20,000 square kilometres down on Wednesday.
But Australian ship Ocean Shield is focused on an area of the Indian Ocean 2,280 kilometres (1,400 miles) northwest of Perth where it picked up two fresh signals Tuesday to match a pair of transmissions logged over the weekend as searchers try to pinpoint the exact crash zone.
No debris from the Boeing 777 which disappeared on March 8 has yet been found.
A large number of objects were spotted on the surface on Wednesday, JACC said, "but only a small number were able to be recovered.
"None of the recovered items were believed to be associated with MH370."
Officials had feared that the signals which were initially picked up might not be detected again, particularly since the batteries on the black box tracking beacons have a normal lifespan of about 30 days.
"Yesterday's signals will assist in better defining a reduced and much more manageable search area on the ocean floor," Houston told a press conference.
"I believe we are searching in the right area but we need to visually identify the aircraft before we can confirm with certainty that this is the final resting place of MH370."
Houston, however, again urged caution for the sake of the families of those aboard the flight which mysteriously vanished en route from Kuala Lumpur to Beijing with 239 people on board, and said the search for more signals would go on.
"Hopefully with lots of transmissions we'll have a tight, small area and... in a matter of days we'll be able to find something on the bottom that might confirm that this is the last resting place of MH370," he said.
Bluefin-21 poised... but 'pings' have stopped
Ships searching for underwater signals from Flight MH370 have heard no more "pings" and will spend several more days trying to pinpoint a crash site before launching a mini-sub to scour the ocean floor, authorities say.
A month to the day since the Boeing 777 vanished with 239 people on board, time is running out to detect further signals as the batteries in beacons on the jet's black box data recorders reach their expiry date.
Transmissions picked up by Australia's Ocean Shield ship consistent with those from aircraft black boxes had raised hopes that a robotic submersible would soon be sent down to look for debris.
But search chief Angus Houston clarified Tuesday that while the pings were an exciting development, further transmissions were needed before scouring the ocean floor.
"We need to continue that (search) for several days to the point at which there is absolutely no doubt that the pinger batteries will have expired," Houston said.
"Until we stop the pinger search we will not deploy the submersible."
He said that no further transmissions had been detected in the remote search area off western Australia which could help pinpoint where the jet carrying 239 people might have crashed.
The plane went missing en route from Kuala Lumpur to Beijing on March 8 and the search is now focusing on a 600-kilometre (370-mile) arc of the remote southern Indian Ocean.
Houston had indicated that the time was nearing for the Ocean Shield, which is criss-crossing the area to try to home in on the signals again, to launch the US-made autonomous underwater vessel Bluefin-21.
But he put a more definitive timeframe on it Tuesday, saying the five-metre (16-feet) long submersible sonar device would not be put into the water unless more transmissions were detected.
"If we go down there now and do the visual search it will take many, many, many days because it's very slow, very painstaking work to scour the ocean floor," he said.
Families of MH370 passengers in Beijing marked the one-month anniversary of the plane's disappearance with a tearful candlelit vigil Tuesday, desperately trying to comfort each other as their agonising wait for news continues.
About two-thirds of the 239 people on board were Chinese.
Sub-marine hunter
The hunt for missing Malaysian Flight MH370 could soon head to the ocean floor using an autonomous sonar vessel after possible black box signals were detected, the head of the Australian-led search operation said Tuesday.
A month to the day since the Boeing 777 disappeared, retired Air Chief Marshal Angus Houston warned that hopes of finding surface debris were fading and that sonic "pings" detected by the Australian naval ship Ocean Shield were the best lead.
Houston told ABC radio Tuesday that once the position of the signals was pinpointed, autonomous underwater vessel Bluefin-21 would be deployed to the ocean floor to search for wreckage.
And this could happen soon.
"I haven't had the discussion this morning, we'll be having that discussion a little later on," he told ABC radio.
"I imagine we'd be getting very close to that point."
The search is now focusing on a 600-kilometre (370-mile) arc of the southern Indian Ocean, far off the West Australian coast.
Houston announced Monday that Ocean Shield had detected underwater signals consistent with aircraft "black boxes", calling it the "most promising lead" so far.
The apparent signals breakthrough came as the clock ticks past the 30-day lifespan of the emergency beacons of the two data recorders from the Malaysia Airlines jet, which vanished on March 8 with 239 people on board en route from Kuala Lumpur to Beijing.
"As a consequence there is a chance the locator beacon is about to cease transmission, or has ceased transmission," Houston said.
"I think it's absolutely imperative to find something else and hopefully when we put the autonomous vehicle down, its capability is such that it'll be able to find wreckage.
"Unfortunately with the passage of time, oceanic drift and all the rest of it -- particularly as a cyclone went through that area in the last few days -- the chances of finding anything on the surface are diminishing with time."
Houston explained that the 4,500m depth of the ocean floor was the absolute operating limit for a Bluefin-21, which is designed for deep sea surveying and can carry video cameras.
"It can't go deeper than that, so it's quite incredible how finely balanced all of this is," he said.
"It's a long, painstaking process, particularly when you start searching the depths of the ocean floor."
Up to eleven military planes, three civilian planes and 14 ships were Tuesday set to take part in the unprecedented search 2,200 kilometres northwest of Perth.
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