Investigations into the mystery of a missing Malaysian jet appeared to be at a deadlock, with no conclusive evidence of foul play.
Eleven days have passed since Malaysia Airlines Flight MH370 went missing. As of Wednesday, 26 nations are still struggling to find the airliner over an area more than two-thirds the size of continental United States.
Malaysian and US officials believe the aircraft was deliberately diverted, but an exhaustive background search of the 239 passengers and crew aboard has not yielded any possible motive.
Malaysia's top official in charge of the unprecedented operation said it was vital to reduce the scale of the search
and renewed appeals for sensitive military data from its neighbours that Malaysia believes may shed light on where the airliner flew.
"All the efforts must be used to actually narrow the corridors that we have announced - I think that is the best approach to do it. Otherwise we are in the realm of speculation again," Malaysia's Acting Transport Minister Hishammuddin Hussein told reporters late on Tuesday.
The search covers a total area of 7.68 million sq km, from central Asia to the southern Indian Ocean.
Due to its size, scale of human loss and sheer uncertainty over what happened, the missing airliner looks set to establish itself as one of the most baffling air transport incidents of all time.
Investigators piecing together patchy data from military radar and satellites, however, believe that someone turned off vital datalinks and turned west, re-crossing the Malay Peninsula and following a commercial route towards India.
After that, short 'pings' picked up by one commercial satellite suggest the aircraft flew on for at least six hours, but investigators have very little idea whether it turned north or south, triggering a search expanding across two hemispheres.
In the latest of a series of possible sightings of the plane, police in the Indian Ocean island chain of the Maldives said they were investigating reports that people on one of its outer islands had seen a low-flying aeroplane there early on March 8. The police gave no further details.
Malaysia Airlines Chief Executive Ahmad Jauhari Yahya said the fact that aircraft continued to exchange electronic "handshakes" with the satellite weighed against theories that the pilots were battling some kind of technical problem.
A breakthrough in the search process is still possible, experts say.