Malaysia's military believes a missing airliner flew hundreds of kilometres off course after its last contact with air traffic control, and rules out terrorism links to fake passports.

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  • Military radar suggests plane turned back and flew some distance off course to the west
  • Interpol believe disappearance of Malaysia Airlines plane was not a terrorist incident
  • Police chief and Interpol say two men holding false passports were Iranian nationals, named as Nour Mohammad Mehrdad and Delvar Suyed Mohammad Reza
  • The pair had swapped their passports in Kuala Lumpur and used stolen Italian and Austrian passports

Malaysia's military said it believed that a jetliner missing for almost four days had turned and flown hundreds of kilometres to the west after it last made contact
with civilian air traffic control off the country's east coast.

A massive search operation for the Malaysia Airlines Boeing 777-200ER has so far found no trace of the aircraft or the 239 passengers and crew.

A senior military officer told Reuters: "It changed course after Kota Bharu and took a lower altitude. It made it into the Malacca Strait."

The Strait of Malacca, one of the world's busiest shipping channels, runs along Malaysia's west coast. When it lost contact with civilian air traffic control, the plane was roughly midway between Malaysia's east coast town of Kota Bharu and the southern tip of Vietnam, flying at 35,000 ft (10,670 metres).

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Earlier on Tuesday, officials ruled out the theory that the two men travelling on false passports were linked to terrorism.

Police chief Khalid Abu Bakar named one of the men travelling on a false passport as Pouria Nour Mohammad Mehrdad, 18, and said he was probably migrating to Germany.

Interpol named the second man as Delavar Seyed Mohammadreza, 29.

'No terror link'

Mr Bakar said: "To date we have uncovered two passengers which was travelling on a stolen passport.

"We have identified one of them... and this one that we have identified is an Iranian by the name of Pouria Nour Mohammad Mehrdad.

"He is 19 years old and he is an Iranian - we believe that he is an Iranian. We have been checking his background. We have also checked him with other police organisation on his profile, and we believe that he is not likely to be a member of any terrorist group.

"And we believe that he is trying to migrate to Germany."

'Psychological problems'

Police have also said they were investigating whether any passengers or crew on the plane had personal or psychological problems that might explain its disappearance, along with the possibility of a hijack, sabotage or mechanical failure

Mr Bakar also said they were looking at whether "psychological problems" of passengers or crew played a role in MH370's disappearance.

He said: "We are looking into four areas. One is hijacking, two sabotage, three psychological problem of the passengers and crew, and four: personal problems among the passengers and crew."

The head of international police agency Interpol later said he did not believe the disappearance of a Malaysia Airlines plane was a terrorist incident.

"The more information we get, the more we are inclined to conclude it is not a terrorist incident," said Interpol Secretary General Ronald Noble.

Meanwhile, the search was widened on Tuesday to a larger swathe of the Gulf of Thailand and the South China Sea, around where the plane lost radio contact and vanished from radar screens.

But searches were also being conducted on the western coast of Malaysia and up north-west towards the Andaman Sea - based on a theory that the plane may have flown on for some time after deviating from its flight path.

Even that information has not been clearly confirmed, and investigators and intelligence sources say the fate of Malaysia Airlines flight MH370 is still shrouded in mystery.