The search is now 11 days old, but military personnel from 26 countries appear to be no closer to finding the missing Malaysian passenger jet.
Malaysian authorities say the search for the Boeing 777 airliner with 239 people aboard has been expanded to cover more than seven million square kilometers. That is an area about the size of Australia and extends from Central Asia in the north to the vast waters of the Indian Ocean to the south.
Thailand's military released new radar information Tuesday that could support earlier reports that the Malaysia Airlines jet made a sharp turn to the west toward the Strait of Malacca after its last contact was recorded early March 8 north of Malaysia. The plane was on a scheduled flight from Kuala Lumpur to Beijing.
The Thai government said its radar detected a plane that may have been the missing Flight 370, but initially paid little attention to the jet because it was not a threat to its security.
Malaysian Defense Minister Hishammuddin Hussein called for more international cooperation in helping narrow the search. Authorities believe the jet was deliberately diverted and flown either toward Central Asia or over the Indian Ocean.
Authorities have refused to rule out any possibility, including terrorism, hijacking, a mechanical malfunction or pilot suicide.
Beijing said none of the plane's 154 Chinese passengers appear to have links to terrorism or hijacking.
Huang Huikang, China's ambassador to Malaysia, said extensive background checks were completed on the passengers from the mainland.
"China has conducted a thorough investigation on the background (of Chinese passengers aboard). So far, (China) has not found any actions that jeopardized Malaysia Airlines MH 370 flight. So we can rule out the possibilities of Chinese passengers suspected of being involved in any kind of terror or jeopardizing activities."
The ambassador also said China has begun looking for the aircraft "in the territory along the northern corridor" of the search area.
Meanwhile, the New York Times is reporting the plane's intended route appears to have been altered by a computer system mostly likely programmed by someone in the cockpit with knowledge of advanced aircraft systems.
Speaking anonymously, U.S. officials told the Times the development reinforces the theory that foul play is involved and will likely increase scrutiny of the plane's pilot and co-pilot.
The search has been complicated because the plane's transponder, which identifies it to civilian radar, and other communications devices were disabled or shut off. Authorities are now forced to rely on imprecise satellite tracking data based on automated messages from the aircraft.
The search area is now so extensive that the U.S. on Monday called back the USS Kidd, a naval destroyer that had been looking for the plane in the Indian Ocean. U.S. officials say it makes more sense to look for the jet using long-range surveillance aircraft.