15/03/2014 11:31 GMT | Updated 15/03/2014 11:59 GMT

Malaysia Airlines MH370 Experienced Bizarre Altitude Changes, New Data Claims

Bloomberg via Getty Images
Aircraft operated by Malaysian Airline System Bhd. (MAS) and PT Lion Mentari Airlines (Lion Air) stand shrouded in haze at Kuala Lumpur International Airport (KLIA) in Sepang, Malaysia, on Friday, March 14, 2014. Indian forces expanded the search for missing Malaysian Airlines Flight 370 to the Bay of Bengal after evidence mounted the plane with 239 people on board may have flown long after controllers lost contact with it a week ago. Photographer: Charles Pertwee/Bloomberg via Getty Images

A startling new report has claimed the missing Malaysia Airlines plane experienced significant changes in altitude after it lost contact with ground control.

The new information follows earlier indications that Flight MH370 deliberately altered its direction after disappearing.

One or more people with significant flying experience hijacked the missing Malaysia Airlines jet, switched off communication devices and steered it off-course, a Malaysian government official involved in the investigation said Saturday.

A New York Times report, citing unnamed American officials and people familiar with the investigation, added further questions to one of the most baffling aviation mysteries of our time.

The plane altered its course more than once as if still under the command of a pilot, American officials and others familiar with the investigation said Friday, the New York Times reported.

Radar signals recorded by the Malaysian military appeared to show that the missing airliner climbed to 45,000 feet, above the approved altitude limit for a Boeing 777-200, soon after it disappeared from civilian radar and turned sharply to the west, according to a preliminary assessment by a person familiar with the data.

The radar track, which the Malaysian government has not released but says it has provided to the United States and China, showed that the plane then descended unevenly to 23,000 feet, below normal cruising levels, as it approached the densely populated island of Penang.

Investigators have also examined data transmitted from the plane’s Rolls-Royce engines that showed it descended 40,000 feet in the span of a minute, according to a senior American official briefed on the investigation.

But investigators do not believe the readings are accurate because the aircraft would most likely have taken longer to fall such a distance.

“A lot of stock cannot be put in the altitude data” sent from the engines, one official said. “A lot of this doesn’t make sense.”

Earlier, there were scenes of frustration as families members demanded answers from officials who said they couldn't take questions.

China is also said to be furious that it has taken a week for Malaysia to brief the public that flight MH370 was deliberately turned off course after its communication system was manually shut down.

China's Xinhua state news agency said that Malaysian PM Mr Najib's announcement today was "painfully belated".

Over a week after the plane disappeared, twelve countries have now joined the massive and widening sweep of the region involving scores of aircraft and ships.

The search operation has now been focused on two corridors, one which extends from north west from Thailand to the Kazakstan-Turkmenistan border and the other which opens out into the southern Indian Ocean.

Malaysian Prime Minister Najib Razak declared on Saturday morning that "deliberate" actions were likely taken by someone on the missing passenger jet Flight MH370.

Evidence is "consistent with the deliberate action of someone on the plane," Razak said, adding that the investigation is "entering a new phase," with search operations ending in the South China Sea.

Malaysia Airlines Flight Disaster In Pictures