Authorities are looking at a possibility that MH370 attempted to turn back toward Kuala Lumpur. If it did indeed retrace its path, the plane could conceivably have crashed into the sea on the western coast, the other side of Malaysia from where it was reported missing. But this doesn't explain why it did not continue to show on radar while flying back toward Kuala Lumpur, and Malaysia Airlines or other authorities have not addressed that question.
"All angles are being looked at. We are not ruling out any possibilities," is all that the Malaysia Airlines statement said.
Malaysia's air force chief also said Sunday there were indications on military radar that the jet may have done a U-turn.
Potential clues discovered during the search have failed to bring authorities closer to the missing plane. Samples from an oil slick – as well as an orange object spotted floating in the ocean – had nothing to do with the plane wreckage, authorities said.
The Associated Press contributed to this report.