What happened yesterday?
An AirAsia flight travelling between Indonesia and Singapore went missing with 162 people on board.
The company said ground control lost contact with flight QZ8501 over the Java Sea after it made a request for a “deviation” from its usual path because of bad weather.
A search and rescue operation took place for several hours yesterday before being called off because of the fading light and poor weather conditions.
What are the latest updates?
Australian search planes say they have have spotted objects in the sea in the "area of interest". Officials have however said these objects are "insufficient evidence" that the debris was linked to the AirAsia jet.
The search party has increased today with planes and ships from several countries taking part and the search area itself has been expanded.
Meanwhile, Singaporean officials have issued a warning that the plane is now most probably 'at the bottom of the sea'.
What do they think caused the plane's disappearance?
In this thorough Q&A for the Independent, travel editor Simon Calder points out that most observers believe it to be an accident. Weather conditions will be one of the main areas investigators look at and they may look at turbulence or lightning as possible causes.
However, he also warns that rumours and theories will do nothing to ease the pain of grieving relatives.
Aviation expert Geoffrey Thomas believes the pilot was ensnared by bad weather and the aircraft may have stalled as he attempted to escape the thunderstorm by climbing higher.
The QZ8501 was flying too slow, about 100 knots which is about 160kmh too slow. At that altitude that’s exceedingly dangerous,” Mr Thomas told reporters.
Essentially the plane is flying too slow to the altitude and the thin air, and the wings won't support it at that speed and you get a stall, an aerodynamic stall," he added.
- Geoffrey Thomas, aviation expert
Australian prime minister Tony Abbott has said it would be "a big mistake" to compare this disappearance to that of MH370 - the Malaysia Airlines flight that is yet to be found after disappearing in March while flying from Kuala Lumpur to Beijing.
MH370, as things stand, is one of the great mysteries of our time. It doesn't appear that there's any particular mystery here.
It's an aircraft that was flying a regular route on a regular schedule, it struck what appears to have been horrific weather, and it's down.
- Tony Abbott, Australian prime minister
The Foreign and Commonwealth Office has confirmed there was a British passenger on board. He has been named in local reports as businessman Chi Man Choi. You can read the Independent’s profile of him here.
Another family of nine were reportedly booked to travel on flight QZ8501 but did not check in in time to board it.
I was shocked to hear about it and cried. Maybe it is all God's plan that my family and I were not on the flight. It was a blessing in disguise.
- A member of the Christianawati family
The father of the pilot of missing AirAsia flight QZ8501 last saw his son just days ago, at the funeral of one of his other sons.