The mystery has the attention of world: What happened to Malaysia Airlines Flight 370?
Dozens of ships and planes from a number of countries, including the United States, have been scouring the area where the Boeing 777 vanished Saturday morning while en route from Kulala Lumpur, Malaysia, to Beijing.
The search area widened Monday to a 115-mile radius from where the jetliner lost contact with air traffic controllers.
Relatives of the 239 people on board held vigils Monday in Kuala Lumpur and Beijing and tried to comfort one another during the painful and frustrating wait for news.
What appeared to be clues have turned out to be false leads. A giant oil slick spotted in the South China Sea was tested, but results showed it was not from the missing jetliner. Nor was a piece of debris that, at first, appeared to be an airplane window.
No distress signals were sent from the plane, but radar indicates Flight 370 may have turned back before losing contact with air traffic controllers.
Two passengers traveling with stolen passports - on tickets purchased from the same travel agent in Thailand - are now a key focus of the investigation.
But the lack of answers is only adding to the misery of waiting family members.
Malaysia Airlines called Bajc nine hours after Wood's flight was scheduled to land.
"My son had to tell me to tell me to turn my computer off," Bajc said. "He put me on a schedule, you know? You can only look at the news so often. It makes you crazy!"
The couple was planning to relocate to Malaysia. Movers were to come hours after Wood's flight was set to land in Beijing.
With no answers, Bajc says she's just clinging to hope.
"Until there's proof that Philip is dead, I refuse to believe it," she said. "If there's anybody that could survive something like this, it's him. I mean, he's such a fighter and he has so much to live for."
Two-thirds of the passengers were Chinese and as time passes, frustration is mounting in Beijing.
In Kuala Lumpur, a team for the National Transportation Safety Board has arrived. Now they are just waiting to find a location where they'll start their investigations.
Both Malaysia Airlines and the Boeing 777 have excellent safety records, leading many to wonder about the possibility of terrorism.
Law enforcement sources say there is no evidence, so far, pointing to terrorism. Intelligence officials say there have been no credible claims of responsibility from any terror group. And so-called "intel chatter" has revealed nothing pointing to an attack on the flight.
Investigators desperately need to find and recover the plane's wreckage and black-box recorders to pin down what was going on with the pilots and their airplane in the critical moments before it was lost.
Authorities are looking at the two men who used stolen passports to board the flight. Police said an Iranian middleman bought the men tickets in Thailand. Each man had a one-way fare to fly from Malaysia to Beijing and then on to Europe.
Police have airport surveillance pictures of the two travelers and their thumbprints. The FBI is expected to check that information against criminal and terror databases. Sources say authorities have identified "partial names" for the men.and have found no ties to terrorism.
Sources say it's likely the men were involved in a human-trafficking operation that moves refugees to Europe.
Perhaps the greatest clue pointing away from terrorism and toward a possible accident is the lack of a widespread field of crash debris. When Pan Am Flight 103 was bombed over Lockerbie, Scotland, in 1988, that plane was ripped apart in flight, spreading wreckage over an 80-mile trail.
The absence of any floating debris in this case is an indicator that Malaysia Airlines Flight 370 may not have disintegrated in midair but rather hit the water intact.