Australian officials searching for the still-missing plane from Malaysia Airlines Flight 370 now believe that the plane was flying on autopilot for hours until it ran out of fuel and crashed. Officials are also considering a theory that the crew was unconscious because of oxygen deprivation.

According to a new report by the Australian Transport Safety Bureau, data from previous crashes and accidents would suggest that the plane spent its final hours on autopilot after the crew fell unconscious from hypoxia. From the Guardian:

It says the loss of MH370 most resembles flights including the Helios Airways "ghost flight" of 2005, which flew for two hours on autopilot after air pressure dropped and its pilots lost consciousness before crashing into a mountain 25 miles north of Athens.

Chief commissioner of ATSB, Martin Dolan, said it was "highly, highly likely" that MH370 was on autopilot for hours before it crashed, because of the orderly path the plane took.

The assumptions have been made as investigators redefine the search area for the plane further south in the Indian Ocean. Searchers will spend three months mapping previously uncharted waters before a detailed underwater search can take place.

With the new data from the report, the search team will now focus on a new area of the Indian Ocean (pictured above) where they hope to find the plane. Officials, though, hedge that it could still take months before they find anything. Australian Deputy Prime Minister Warren Truss tells CNN:

Truss said an international team of experts had chosen the 60,000-square-kilometer zone, an area roughly the size of West Virginia, after going over all the available data.

"This site is the best available and most likely place where the aircraft is resting," he said.

He warned, though, that the operation to comb the sea floor in the area, which has never been fully mapped, would be "very challenging and complex."

"We could be fortunate and find it in the first hour, or the first day," he said. "But it could take another twelve months."

[Image of new search area via the Guardian]