U.S. says missing Malaysian jet could be 'act of PIRACY': Evidence shows plane changed direction and climbed to 45,000 feet 'under command of a pilot' after tracking devices were manually disabled

Sources: Plane may have been deliberately flown across Malay peninsula

Military radar-tracking evidence reportedly suggests it was heading towards the Andaman Islands

US inquiries are increasingly focusing on theory someone who knew how to fly a plane deliberately diverted the flight, according to reports



Investigation sources also say plane may have climbed to more than 45,000ft immediately after losing contact - higher than the plane is allowed

Rival theory: Cargo of batteries could have caught fire, downing the plane



Search efforts are now being stepped up in the Andaman Sea and Indian Ocean

A U.S. official has said investigators are examining the possibility that the disappearance of a Malaysia Airlines jet was 'an act of piracy'.

Key evidence for 'human intervention' is that even after the plane's transponder ceased contact an hour into the flight, a routine monitoring system sent a message to a satellite indicating that the plane had turned to the west in a dramatic change of direction - before that system, too, was disabled.



While theories continue to swirl round the vanishing of flight MH370, the probe has sharpened its focus on sabotage.

'Increasingly, it seems to be heading into the criminal arena,' former member of the U.S. National Transportation Safety Board Richard Healing told the Wall Street Journal. He said the latest theories 'indicate the emphasis is on determining if a hijacker or crew member diverted the plane.'



New Malaysian military radar evidence shows the plane climbed to 45,000ft - 2,000ft above a Boeing 777's recommended limit - which could have knocked its passengers unconscious in a deliberate attack.



Other theories state the plane's cargo of highly flammable lithium batteries could have ignited, that it was crashed as a pilot's suicide or even that it landed safely in a secret location.

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Theories: Suspicions are increasing that flight MH370 was deliberately diverted, as evidence suggests it took a sharp turn to the west and headed out over the Andaman Islands, sources have claimed

If the plane did carry on flying for five hours it could have travelled 2,200 nautical miles Two sources told Reuters an unidentified aircraft, which investigators believe was Flight MH370, was following a route between navigational waypoints - indicating it was being flown by someone with aviation training - when it was last plotted on military radar off the country's north west coast (file picture)

Two sources familiar with the investigation said an unidentified aircraft - which investigators believe was flight MH370 - was plotted by military radar following a route between navigational waypoints.

This indicates that it was either being flown by the pilots or someone with knowledge of those waypoints, the sources said.

Military officer Nguyen Tran looks out from a Vietnam Air Force AN-26 aircraft during a mission to find the missing Malaysia Airlines flight MH370, off Con Dao island

The last plot on the military radar's tracking suggested the plane was flying towards India's Andaman Islands, a chain of isles between the Andaman Sea and the Bay of Bengal, they said.

Waypoints are geographic locations, worked out by calculating longitude and latitude, that help pilots navigate along established air corridors.

A senior Malaysian police official said: 'What we can say is we are looking at sabotage, with hijack still on the cards.'

Security officials are also looking at whether multiple people would have been needed to turn the plane off course, the Journal reported.



Turning off the plane's signaling system may have also required someone to access into the plane's electronics bay on the lower deck.



All the sources, quoted by various news agencies, declined to be identified because they were not authorised to speak to the media.



The U.S. Navy 7th Fleet said it was moving one of its ships, the USS Kidd, into the Strait of Malacca (file picture)



Malaysian Transport Minister Hishammuddin Hussein said he could not confirm the last heading of the plane or if investigators were focusing on sabotage. 'A normal investigation becomes narrower with time... as new information focuses the search, but this is not a normal investigation,' he told a news conference. 'In this case, the information has forced us to look further and further afield.'

MYSTERY OF 'DEACTIVATED TRANSPONDER'

An unanswered question is what exactly happened to the Boeing 777's transponder.

Transponders are devices that emit electronic signals containing information that shows up on air traffic controllers' screens. The information includes the plane's unique identifying code and its direction, speed and altitude.

In the case of the Malaysian jetliner, the transponder stopped about an hour after takeoff.

Ross Aimer, an industry consultant and former airline pilot, says the 777 has two transponders, one a backup. If one goes out, the other comes on automatically. He says both can be shut off by turning a single knob on the cockpit panel. This would make the plane more difficult to track - but not impossible, he explained.

Investigators were still looking at 'four or five' possibilities, including a diversion that was intentional or under duress, or an explosion, he said.

Police would search the pilot's home if necessary and were still investigating all 239 passengers and crew on the plane, he added. It came shortly after an aviation expert suggested that pilot suicide could be an explanation, citing previous incidents in the 1990s.

Mike Glynn, a committee member of the Australian and International Pilots Association, cited a SilkAir crash during a flight from Singapore to Jakarta in 1997 and an EgyptAir flight in 1999.

'A pilot rather than a hijacker is more likely to be able to switch off the communications equipment,' Glynn said.

'The last thing that I, as a pilot, want is suspicion to fall on the crew, but it's happened twice before.'

Glynn said a pilot may have chosen to fly the plane into the Indian Ocean to reduce the chances of recovering data recorders, and to conceal the cause of the disaster. Malaysian police have previously said they were investigating whether any passengers or crew had personal or psychological problems that might shed light on the mystery, along with the possibility of a hijacking, sabotage or mechanical failure. As a result of the new evidence, the sources said, multinational search efforts were being stepped up in the Andaman Sea and also the Indian Ocean. Another source speaking to the New York Times suggested a rival line of enquiry - that a cache of batteries being transported on the plane caught fire and brought it down. The U.S. source said a 'significant load' of Lithium batteries - which are prone to catching fire, and burn with an intense heat - were among the plane's cargo. Such accidents have brought down planes in the past, but the theory is at odds with the growing consensus that the plane kept flying for hours after its last known contact.

The Wall Street Journal reported yesterday that 'pings' sent from missing flight 370 provided the plane's location, speed and altitude for at least five hours after it vanished from radar. If the plane did carry on flying for that time it could have travelled 2,200 nautical miles, possibly reaching north-western India and the border with Pakistan. Sources have claimed missing flight MH370 could have been deliberately flown across the Malay peninsula. Pictured is the engine of a Vietnamese Air Force Russian-made AN-27 as it returns from a search operation over Vietnam's southern sea

A P3C patrol plane of the Japan Maritime Self-Defense Force sits on the taxi way at Sepang air force base, Malaysia

As one of the most baffling mysteries in the history of modern aviation remains unsolved after nearly a week, the latest radar evidence is consistent with the expansion of the search for the aircraft to the west of Malaysia.

There has been no trace of the plane, nor any sign of wreckage as the navies and military aircraft of more than a dozen countries scour the seas across south east Asia.

India today began searching hundreds of uninhabited islands in the Andaman Sea, using heat-seeking devices.



Two Indian air force reconnaissance planes began flying over the islands as a precaution, after they and two naval ships scoured the seas surrounding the Andaman and Nicobar Islands, according to spokesman Col. Harmit Singh of India's Tri-Services Command on the territory.



The archipelago that stretches south of Myanmar contains 572 islands covering an area of 720 by 52 kilometers. Only 37 are inhabited, with the rest covered in dense forests.

Malaysian Acting Transport Minister Hishammuddin Hussein attended prayers for passengers and crew of missing Malaysia Airlines flight MH370 at a mosque near Kuala Lumpur International Airport

Friday prayers are said at the KLIA Mosque near the Kuala Lumpur International Airport

India today began searching hundreds of uninhabited islands in the Andaman Sea, using heat-seeking devices, officials said

Prayers are said for passengers and crew of missing Malaysia Airlines flight MH370 at the mosque near Kuala Lumpur International Airport, Malaysia

The Indian navy is also considering expanding its search west into the Bay of Bengal.



'We are awaiting permission from the Navy,' he said, but declined to give details about the rest of the search operation, including the use of technologies such as the heat sensors aboard the Dornier planes.



Coast Guard official V.S.R. Murthy said India would turn its focus toward western waters between the islands and the Indian coast. On Friday, two navy ships were still sailing east of Great Nicobar Island.



The White House said the U.S. may be drawn into a new phase of the search in the vast Indian Ocean but did not offer details. The U.S. Navy 7th Fleet said it was moving one of its ships, the USS Kidd, into the Strait of Malacca.



'It's my understanding that based on some new information that's not necessarily conclusive - but new information - an additional search area may be opened in the Indian Ocean,' White House spokesman Jay Carney told reporters in Washington.

Carney did not specify the nature of the new information.

Relatives of Chinese passengers aboard missing Malaysia Airlines flight MH370 speak to journalists at a hotel in Beijing A man rests inside a room reserved for relatives of Chinese passengers aboard the missing Malaysia Airlines flight MH370 at a hotel in Beijing

A man calls on his phone inside a room reserved for relatives of Chinese passengers aboard the missing Malaysia Airlines flight MH370 at a hotel in Beijing

A statement from Malaysia's ministry of transport said it was following all leads that might help locate the aircraft.

Satellites picked up faint electronic pulses from the aircraft after it went missing on Saturday, but the signals gave no immediate information about where the jet was heading and little else about its fate, two sources close to the investigation said.

U.S. experts are still examining the data to see if any information about its last location could be extracted, a source close to the investigation told Reuters.

The 'pings' indicated its maintenance troubleshooting systems were switched on and ready to communicate with satellites, showing the aircraft was at least capable of communicating after losing touch with air traffic controllers.

The system transmits such pings about once an hour, according to the sources, who said five or six were heard.

However, the pings alone are not proof that the plane was in the air or on the ground.

Pilots on board a Vietnamese Air Force Russian-made AN-27 aircraft search Vietnam's southern sea for missing Malaysia Airlines' flight MH370

A Vietnamese military official looks out of a window inside a plane of the Vietnam Air Force during search and rescue operations

The last sighting of the aircraft on civilian radar screens came shortly before 1.30am Malaysian time last Saturday, less than an hour after it took off from Kuala Lumpur, as the plane flew northeast across the mouth of the Gulf of Thailand. That put the plane on Malaysia's east coast.

Malaysia's air force chief said on Wednesday an aircraft that could have been the missing plane was plotted on military radar at 2.15am, 200 miles (320 km) northwest of Penang Island off Malaysia's west coast.

This position marks the limit of Malaysia's military radar in that part of the country, a fourth source familiar with the investigation told Reuters.

When asked about the range of military radar at a news conference on Thursday, Malaysian Transport Minister Hishammuddin Hussein said it was 'a sensitive issue' that he was not going to reveal.

'Even if it doesn't extend beyond that, we can get the co-operation of the neighbouring countries,' he said.

The fact that the aircraft - if it was MH370 - had lost contact with air traffic control and was invisible to civilian radar suggested someone on board had turned off its communication systems, the first two sources said.

Malaysian Muslims offer Friday prayers during a special prayer session for passengers of the missing Malaysia Airlines flight MH370 plane at the Kuala Lumpur International Airport mosque

In one of the most baffling mysteries in modern aviation, no trace of the plane nor any sign of wreckage has been found despite a search by the navies and military aircraft of more than a dozen countries

Muslims pray during Friday prayers at the National Mosque in Kuala Lumpur

They also gave new details on the direction in which the unidentified aircraft was heading - following aviation corridors identified on maps used by pilots as N571 and P628. These routes are taken by commercial planes flying from Southeast Asia to the Middle East or Europe and can be found in public documents issued by regional aviation authorities.

In a far more detailed description of the military radar plotting than has been publicly revealed, the first two sources said the last confirmed position of MH370 was at 35,000 feet about 90 miles (144 km) off the east coast of Malaysia, heading towards Vietnam, near a navigational waypoint called 'Igari'. The time was 1.21am.

The military track suggests it then turned sharply westwards, heading towards a waypoint called 'Vampi', northeast of Indonesia's Aceh province and a navigational point used for planes following route N571 to the Middle East.

From there, the plot indicates the plane flew towards a waypoint called 'Gival', south of the Thai island of Phuket, and was last plotted heading northwest towards another waypoint called 'Igrex', on route P628 that would take it over the Andaman Islands and which carriers use to fly towards Europe.

The time was then 2.15am. That is the same time given by the air force chief on Wednesday, who gave no information on that plane's possible direction.

A Vietnamese military official takes notes as he looks through a window of a Vietnam Air Force plane during search and rescue operations for a missing Malaysian Airlines flight, off Vietnam's sea

A cabin crew of the Vietnam Air Force is seen onboard a flying AN-26 Soviet made aircraft during a search operation for the missing Malaysia Airlines flight MH370

Col. Vu Duc Long of the Brigade 918, Vietnam Air Force answers to the media after a search operation for the missing Malaysia Airlines flight MH370 plane

The sources said Malaysia was requesting raw radar data from neighbours Thailand, Indonesia and India, which has a naval base in the Andaman Islands.

A senior government official said Malaysia is working with U.S. investigators to establish if there is any satellite information that could help locate the airliner.

'They indicated they were studying the possibility of satellite communication. Whatever they have and will share with us,' Azharuddin Abdul Rahman, the head of Malaysia's Civil Aviation Authority, told a news conference.



British investigators from the accident investigation board are also helping examine satellite data.



The U.S. Navy was sending an advanced P-8A Poseidon plane to help search the Strait of Malacca, a busy sealane separating the Malay Peninsula from the Indonesian island of Sumatra. It had already deployed a Navy P-3 Orion aircraft to those waters.

Friday prayers at the National Mosque in Kuala Lumpur included a special prayer session for the passengers of the missing Malaysia Airlines Flight MH370

In one of the most baffling mysteries in modern aviation, no trace of the plane nor any sign of wreckage has been found despite a search by the navies and military aircraft of more than a dozen countries

China, which had more than 150 citizens on board the missing plane, has deployed four warships, four coastguard vessels, eight aircraft and trained 10 satellites on a wide search area.



Chinese media have described the ship deployment as the largest Chinese rescue fleet ever assembled.

The Boeing 777 has one of the best safety records of any commercial aircraft in service.

Its only previous fatal crash came on July 6 last year when Asiana Airlines Flight 214 struck a sea wall with its undercarriage on landing in San Francisco. Three people died in the incident.

China meanwhile has urged Malaysia's government to release any information it has regarding the missing jet to help narrow the search area.

The Foreign Ministry's appeal reflected growing frustration among Chinese officials over conflicting information about the plane.

Malaysian Prime Minister Najib Razak, centre, arrives for Friday prayer at a mosque in Sepang, Malaysia

Malaysian Prime Minister Najib Razak, second from left, offers a prayer at a mosque in Sepang, Malaysia

'China urgently appeals to Malaysia for all information they have regarding the search,' said Foreign Ministry spokesman Hong Lei. 'That will not only help China with its search, but also help all sides in the search to make their search more effective and accurately targeted.'

Eight Chinese vessels are taking part in the international search effort. They covered 21,000sq miles of ocean by Thursday evening and were expanding their search area, according to China's official Xinhua News Agency.

According to reports, Chinese state news agency Xinhua has also reported an 'earthquake wave' had been detected in waters between Malaysia and Vietnam at about at 2.55am.



A Chinese seismology and research group told Xinhua that the 'sea floor event could have been caused by the plane possibly plunging into the sea,' news.com.au has reported.



The area, which is considered to be non-seismic, is reportedly 116km northeast from where the last contact was made with MH370.

According to reports, the plane was equipped with four life rafts and enough food to help those on board survive a week.

A relative of passengers of the missing Malaysia Airlines plane gestures to the media before the start of a conference with airline representatives at a hotel in Beijing

Relatives of passengers of the missing plane try to enter a meeting room for a conference with airline representatives at a hotel in Beijing, China

A spokesman for the airline told relatives during a meeting that the jetliner also had flashlights, first aid kits and drinking water, according to Chinese news outlet ECNS, as cited by the International Business Times.



It was suggested the life rafts could carry up to 290 people.



Frustrated relatives of missing passengers met in Beijing with Malaysia Airlines' commercial director and pressed for clarification of reports about how long the plane emitted signals while flying.

'We don't simply want to get our information from the news media,' one man told the executive, Hugh Dunleavy.

Mr Dunleavy said he could not provide any new information, but that he would work on obtaining updates from search officials.