Investigators believe someone aboard a missing Malaysian airliner deliberately shut off its communications and tracking systems, turned the plane around and flew for nearly seven hours after it vanished. Here is a timeline in pictures about the questions that have baffled investigators. The photos from AP show floral trubutes to passengers, prayers and search missions trying to track the plane.
As the unprecedented search for Flight MH370 and its 239 passengers and crew entered its second week, the hunt for wreckage around the scheduled flight path to the east of Malaysia was being called off.
The plane's last communication with satellites placed it in one of two corridors: a northern corridor stretching from northern Thailand to the border of Kazakhstan and Turkmenistan, or a southern corridor stretching from Indonesia to the southern Indian Ocean.
The fate the of the Malaysian Airlines Boeing 777 has been shrouded in mystery since it disappeared off Malaysia's east coast less than an hour into a March 8 scheduled flight from Kuala Lumpur to Beijing.
But investigators have increasing focused on the possibility that it was flown off-course by the one of the pilots or someone else on board with detailed knowledge of how to fly and navigate a large commercial aircraft.
It appeared most likely the plane turned south over the Indian Ocean, where it would presumably have run out of fuel and crashed into the sea. The other interpretation was that Flight MH370 continued to fly to the northwest and headed over Indian territory.
New data showed the last communication between the missing plane and satellites at 8:11 am Malaysian time.
The disappearance of the Boeing 777 - one of the safest commercial jets in service - is shaping into one of the most baffling mysteries in aviation history.
That is almost seven hours after it dropped off civilian air traffic control screens at 1:22 a.m, less than an hour after take-off. It was flying across the mouth of the Gulf of Thailand on the eastern side of Malaysia towards Vietnam.
Satellite data confirmed that an unidentified aircraft that later appeared on military radar off Malaysia's west coast before going out of range at 2:15 a.m. was flight MH370.
It is extremely rare for a modern passenger aircraft to disappear once it has reached cruising altitude, as MH370 had. When that does happen, the debris from a crash is usually found close to its last known position relatively quickly.
In this case, there has been no trace of the plane, nor any sign of wreckage, as the navies and military aircraft of more than a dozen countries scour the seas on both sides of peninsular Malaysia. The maximum range of the Boeing 777 is 7,725 nautical miles or 14,305 km. It is not clear how much fuel the aircraft was carrying though it would have been enough to reach its scheduled destination, Beijing, a flight of five hours and 50 minutes.