A U.S. official told CNN on Tuesday that a "heat flash" over Egypt's Sinai Peninsula was detected by a military satellite just before the Saturday plane crash that killed 224 people aboard a Russian airliner, the network reports. The account echoes an NBC report sourced to two senior defense officials, and both reports say that the satellite evidence indicates that a "catastrophic in-flight event"—possibly an explosion caused by a bomb or mechanical failure—downed Metrojet Flight 9268. NBC says that it's unlikely that a missile could have caused the crash because the satellite that picked up the flash would have also registered the "heat trail" of a missile but did not; CNN also says the U.S. has ruled out the possibility that the plane was shot down.
Metrojet officials said Monday that they were sure that the crash had not been caused by mechanical failure or pilot error but didn't provide any evidence of that claim. The plane involved, an Airbus A321, dropped some 5,000 feet in a minute before breaking into pieces and never issued a distress call.
Russia, of course, is widely believed to have been behind the downing of Malaysia Airlines Flight 17 over the Ukraine in July 2014, which is only one of the conflicts the country is engaged in that could have motivated a terror bombing. For a sense of how politically fraught efforts to find out what caused the Metrojet crash could end up becoming, consider this Atlantic piece on the crash of EgyptAir 990 off Nantucket (after which Egyptian aviation authorities more or less sabotaged the investigation of what seems to have been a pilot suicide/homicide), this New York Review of Books piece on the 1999 Russia "apartment bombings" (which killed hundreds and were blamed on Chechen terrorists but may have been false-flag attacks planned by Vladimir Putin as he transitioned into power), and this New Yorker piece about the 1988 bombing of Pan Am 103 (which is known to have been planned by Libya but whose actual perpetrators may never have been brought to justice). It could be a long time before we know what happened to Metrojet 9268, or we might never find out at all.