The last words heard by Malaysia Airlines Flight MH370 suggest that everything was normal before the plane inexplicably went missing on Saturday with 239 people on board. This was revealed by Malaysian authorities at a news conference in Beijing, held for relatives of people on the flight. 

According to BBC News, as the plane was traveling towards the boundary of Malaysia and Vietnam, the Malaysian air control told the cockpit that they were handing over to Ho Chi Minh City control. Flight MH370 responded, "All right, roger that," and moments later, the plane and the souls on board were gone.

The plane was travelling from Kuala Lumpur to Beijing, when the aircraft vanished an hour after take-off. Since then, there have been numerous speculations of what might have happened. Explanations range from mechanical failure and hijacking to pilot suicide and terrorist attacks. However, for every situation, experts find a way to prove that these were not the case.

BBC reported that a New Zealander had sent an email to Vietnam's air traffic management, stating he had seen a burning object near the oil rigs off Vung Tau. 

Search investigations have been increased to include air and sea vessels. However, investigators don't know where to look because the last communication between air control and the flight was that everything was "all right."

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