Efforts are being intensified in the search for a Malaysia Airlines jet with 239 people on board which has been missing since Saturday.
Reports of an oil slick in the waters off the southern tip of Vietnam suggest the plane has crashed but sightings of debris remain unconfirmed.
What happened to flight MH 370 when it disappeared one hour into its journey from Kuala Lumpur to Beijing is still a mystery.
Director General of the Malaysia Civil Aviation Authority Dato Azharuddin Abdul Rahman described the extent of the search operation:
“Today, we have used a large number of assets, comprising of 34 aircraft, 40 ships, hundreds of men, thousands of man-hours has been deployed. And countries that assisted us include: Vietnam, China, Singapore, Indonesia USA, Thailand, Australia and the Philippines.”
The authorities are investigating security breaches after Interpol confirmed that at least two passengers used stolen passports.
Nothing is being discounted, from a hijacking to a bombing to a catastrophic technical failure.
Although the Boeing 777 has a good safety record the lack of debris so far would indicate the aircraft may have broken up mid-flight.