More than three days after the last contact with Malaysia Airlines Flight 370, no electronic "chatter" has been detected indicating any known terror group was behind the aircraft's mysterious disappearance.
A senior U.S. official said federal investigators are reviewing surveillance video from the point of origin of the missing flight — along with travel patterns associated with two stolen passports fraudulently used to board the doomed aircraft and any thumbprint records made at security checkpoints.
A source told NBC News that only "wackos" were taking responsibility for the disappearance — the individuals who seem to come out of the woodwork in the wake of global catastrophes.
Al-Qaeda — as well as its affiliates and other groups inspired by its fundamentalist jihad — traditionally seeks credit after perpetrating attacks.
If the aircraft crashed as a result of a terror incident, officials had found no apparent connection Sunday to the U.S., the United Kingdom or another Al-Qaeda target.
The flight carried a large number of Chinese passengers and crew. No group to date is known to have targeted China with an attack as sophisticated as a hijacking or bombing of an airplane.
The two stolen passports bear a troubling travel pattern, according to senior intelligence sources.
In at least one prior instance, the passports were used in tandem to board a flight.
There was an effort underway Sunday to compare airport checkpoint images — if the images are available — from prior points where the documents were used since they were reported stolen or missing.
U.S. officials are still sorting out how and where the fraudulent passengers purchased tickets.
Both ticket holders were traveling through China to connect to a flight to Amsterdam. One of the passengers was then due to connect to Frankfurt with the other en route to Stockholm.
Officials currently believe the tickets were paid for in cash, according to one senior law enforcement official.