On Friday, a Malaysian Air flight bound for Beijing simply disappeared off radar screens over the sea between Kuala Lumpur and Vietnam. The only clues thus far are two oil slicks seen on the South China Sea, but no debris has been found at all and other rumors of a possible emergency landing have proven false. Even the oil slicks themselves might not have any connection to Flight 370; initial tests indicate one of them isn’t. Meanwhile, a Malaysian official confirmed that two passengers used stolen passports to board the flight, and appear to have bought tickets together:

ABC Entertainment News | ABC Business News

Two suspects on Malaysia Airlines Flight MH370 who used stolen passports had no record of entering Malaysia legally, officials say.

Malaysia’s Inspector General of Police, Tan Sri Khalid Abu Bakar, said Monday that the identity of one of the two suspects has been confirmed.

“He is not a Malaysian, but I cannot divulge which country he is from yet,” he said.

Two passengers managed to board the ill-fated aircraft using passports reported stolen in Thailand in recent years, booking their tickets at the same time. The passports belonged to Italian and Austrian residents.

How could passports stolen in Thailand in 2012 and 2013 manage to pass muster at airports? It’s because many countries aren’t checking the Interpol database — a security gap that might have been well enough known to exploit:

The stolen passports could be related to other activities, though, such as drug smuggling. There is also another point to consider: Flight 370 went missing four days ago, and yet there has been no claim of responsibility by any terrorist organization. If the point was to take down an airplane to inspire terror, usually a declaration by the terrorists involved would immediately follow the attack. These days, even if governments wanted to keep that quiet, the groups would know how to get that message out through alternative means — and yet we’ve heard nothing of the kind, not even the attempt to take credit as a PR stunt.

Unless the plane suddenly appears, this mystery will be a long time unraveling, it appears.

Update: The first reports were that the flight was bound for Japan, but it was bound for Beijing. I’ve corrected it above.