Malaysian Prime Minister Najib Razak says investigators now know that the missing Malaysian airliner’s communications were deliberately disabled and that it turned back from its flight to Beijing and flew across Malaysia.
Exactly a week to the day since flight MH370 went missing, he told a packed press conference that the plane's last satellite contact indicates two possible flight corridors which are now the focus of the search - Kazakhstan and Turkmenistan to Northern Thailand, and the southern corridor of Indonesia to the southern Indian Ocean.
He confirmed that the plane's transponders - which send back information to civilian radar regarding performance, location and altitude - were deliberately switched off, but denied that investigators had concluded hijacking as the reason why the jet vanished. However, he did say the aircraft's disappearance was a result of “deliberate action” by someone on board.
Najib was responding to earlier claims on Saturday from a Malaysian government official that investigators had concluded that one of the pilots or someone else with flying experience hijacked the missing Malaysia Airlines jet.
The official, who is involved in the investigation and spoke to Associated Press on condition of anonymity because he was not authorized to brief the media, had said that hijacking was no longer a theory. “It is conclusive.”
But Prime Minister Najib would only go so far as to say that all possibilities were being investigated, before adding: “In view of this latest development, the Malaysian authorities have refocused their investigation into the crew and passengers on board.”
He said that after the transponders were disabled, the aircraft - carrying 12 crew and 227 passengers - turned back and flew in a westerly direction before turning north west.
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He told the press conference: "Earlier this morning I was briefed by the investigation team which includes the FAA, NTST, AAIB, Malaysian authorities and the acting minister of transport on new information that sheds further light on what happened on MH370.
"Based on new satellite communication, we can say with a high-degree of certainty, the aircraft communications addressing and reporting systems or ACARS, was disabled just before the aircraft reached the east coast Peninsula Malaysia. Shortly afterwards near the border between Malaysia and Vietnamese air traffic control, the aircraft’s transponder was turned off.
"From this point onwards the Royal Malaysian Air Force primary radar data showed that an aircraft which was believed but not confirmed to be MH370 did indeed turn back. It then flew in a westerly direction back over Peninsula Malaysia before turning northwest. Up until the point at which it left military primary radar coverage, these movements are consistent with deliberate action by someone on the plane."
He added: "Today, based on raw satellite data, which was obtained from the satellite data service provider, we can confirm that the aircraft shown in the primary radar data was MH370.
"According to the new data, the last confirmed communication between the plane and the satellite was at 08:11am Malaysian time on Saturday, 8th of March.
"However, based on this new data, the aviation authorities of Malaysia and the international counterparts have determined that the plane's last communication with a satellite was in one of two possible corridors. A northern corridor stretching approximately from the border of Kazakhstan and Turkmenistan to Northern Thailand. Or, a southern corridor stretching approximately from Indonesia to southern Indian ocean.
"The investigation team is working to further refine the information."
Relatives of the missing passengers reacted with cynicism.
Responding to the press conference, Wen Wancheng from Shandong, whose son was a passenger on board, told the South China Morning Post: "I think this is a pure conspiracy. The Malaysian authorities didn't treat us honestly. I don't know why they did this to us. The time they gave wasn't right and the location was not correct. They are wasting the time of rescue.
"I feel deeply upset for what they (Malaysian government) have done. They should be more honest to us and other countries that spent tremendous efforts to rescue."
Another, Bian Weiliang, whose elder brother was on board, said: "I feel cheated. They should have released the information (that was released during the press conference) earlier. I don't understand why they are doing this.
"I think this press conference was basically telling us that it's a hijacking. My question is will the MA will continue to take care of us? Or they will abandon us since they kindly said it's not their responsibility."
Relatives earlier told the Post that a Malaysia Airlines representative had said the probe was now a criminal investigation.
According to Reuters, Malaysiam police were today searching the home of the pilot, although it did not specify which.
Today's claims follow a report in the New York Times that Malaysian military radar data showed the jet climbed to 45,000ft, above the approved altitude limit for a Boeing 777-200, soon after its last known position, after making a turn to the west.
Investigators said on Friday they were focusing increasingly on foul play, as evidence suggested the plane turned sharply west after its disappearance and - with its communications systems deliberately switched off - continued to fly for perhaps several hours.
"What we can say is we are looking at sabotage, with hijack still on the cards," said the source, a senior Malaysian police official.
A U.S. source familiar with the investigation said there was also discussion within the U.S. government that the plane’s disappearance might have involved an act of piracy.
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A source familiar with data the U.S. government is receiving from the investigation told Reuters the pulses sent to satellites were ambiguous and had been interpreted to provide two different analyses.
The electronic signals were believed to have been transmitted for several hours after the plane flew out of radar range, said the source familiar with the data.
The most likely possibility is that, after travelling northwest, the Boeing 777-200ER made a sharp turn to the south, over the Indian Ocean where officials think, based on the available data, it flew until it ran out of fuel and crashed into the sea, added the source.
The other interpretation is that Flight MH370 continued to fly to the northwest and headed over Indian territory.
The source added that it was believed unlikely the plane flew for any length of time over India because that country has strong air defence and radar coverage and that should have allowed authorities there to see the plane and intercept it.
Either way, the analysis of satellite data appears to support the radar evidence outlined by sources familiar with the investigation in Malaysia.
Two sources told Reuters that military radar data showed an unidentified aircraft that investigators suspect was Flight MH370 following a commonly used commercial, navigational route towards the Middle East and Europe.
That course - headed into the Andaman Sea and towards the Bay of Bengal in the Indian Ocean - could only have been set deliberately, either by flying the Boeing 777-200ER jet manually or by programming the auto-pilot.
"It could have been done intentionally. It could have been done under duress. It could have happened as a result of an explosion," said Hishammuddin Hussein, Malaysia's acting transport minister.
Meanwhile, a London-based satellite communications company which supplied equipment to the missing plane confirmed on Friday that it had recorded “routine, automatic signals” during the flight, which could help estimate the aircraft’s location.
The information from the company, Inmarsat, could be a turning point for Malaysian investigators and foreign experts drafted to assist with the hunt for the jet.
Aviation experts from the UK – in addition to a team from Rolls-Royce, which manufactured the 777's engines – were due to arrive in Malaysia on Friday night to help with the investigation, said the civil aviation chief, Azharuddin Abdul Rahman.
A total of 57 ships, 48 aircraft and 13 nations are taking part in the search and rescue mission. Indian planes and ships have begun searching the 572 islands comprising the Andaman and Nicobar island groups using heat-seeking devices to help find the missing plane.
US officials said the jet was emitting signals to satellites for hours after its last contact with air traffic control. That opened the possibility that one of the pilots, or someone with flying experience, wanted to hijack the plane for some later purpose, kidnap the passengers or commit suicide by plunging the jet into the sea.
Mike Glynn, a committee member of the Australian and International Pilots Association, said he considered pilot suicide to be the most likely explanation for the disappearance, as was suspected in a SilkAir crash in 1997 and an EgyptAir crash 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."
Watch: Aviation expert considers missing flight MH370 theories
China, which has the most citizens aboard the plane, added another naval ship to the search in the Gulf of Thailand and redeployed a civilian government ship to the Strait of Malacca.
China's deployment to the search and rescue operation, however, has been hampered by limited access to data from Malaysian authorities, said an aviation expert with links to the Chinese government who requested anonymity. The source said that US officials had direct access to details.
Watch: Hunt for missing jets spreads to Indian Ocean
Meanwhile, a team of seismologists with the University of Science and Technology of China in Hefei said that a slight tremor had occurred on the sea floor between Vietnam and Malaysia last Saturday, the day the plane disappeared.
Professor Fu Liyun , seismologist with the Chinese Academy of Sciences' Institute of Geology and Geophysics, said the occurrence might be consistent with a plane crashing into the sea, which would produce "enormous shock waves".