HUGE INTERNATIONAL SEARCH
A huge international search operation has been mostly focused on the shallow waters of the Gulf of Thailand off Malaysia's east coast, although the Strait of Malacca has been included since Sunday.
Navy ships, military aircraft, helicopters, coast guard and civilian vessels from 10 nations have criss-crossed the seas off both coasts of Malaysia without success.
In the absence of any concrete evidence to explain the plane's disappearance, authorities have not ruled out anything. Police have said they were investigating whether any passengers or crew on the plane had personal or psychological problems that might shed light on the mystery, along with the possibility of a hijacking, sabotage or mechanical failure.
"Maybe somebody on the flight has bought a huge sum of insurance, who wants family to gain from it or somebody who has owed somebody so much money, you know, we are looking at all possibilities," Malaysian police chief Khalid Abu Bakar said at a news conference on Tuesday.
The airline said it was taking seriously a report by a South African woman who said the co-pilot of the missing plane had invited her and a female travelling companion to sit in the cockpit during a flight two years ago, in an apparent breach of security.
"Malaysia Airlines has become aware of the allegations being made against First Officer Fariq Ab Hamid which we take very seriously. We are shocked by these allegations. We have not been able to confirm the validity of the pictures and videos of the alleged incident," the airline said in a statement.
The woman, Jonti Roos, said in an interview with Australia's Channel Nine TV that she and her friend were invited to fly in the cockpit by Fariq and the pilot between Phuket, Thailand, and Kuala Lumpur in December 2011. The TV channel showed pictures of the four apparently in a plane's cockpit.
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 seawall on landing in San Francisco, killing three people.
US planemaker Boeing has declined to comment beyond a brief statement saying it was monitoring the situation.