… what exactly did cause the crash of the Metrojet Airbus and the death of all 224 people on board? The charter airline’s deputy general director says that they “rule out a technical fault and any mistake by the crew,” and has concluded that the plane broke up in mid-air. Does that re-open the possibility that a claim by ISIS to have shot down the jet might be true? Or is the executive engaging in speculation to protect his own interests?

The Russian airliner that broke apart in mid-flight over the Sinai peninsula was not caused by any malfunction or pilot error, the airline said Monday, deepening the mystery over the disaster but leaving open probes into some kind of plot or attack.

The latest statements in Moscow gave no indications of the direction of the investigations into Saturday’s crash that killed all 224 aboard. But Alexander Smirnov, deputy general director of the airline, insisted the tragedy could only be the result of some “mechanical impact on the aircraft.”

Dmitri Peskov, the personal spokesman to Russian President Vladimir Putin, said that an act of terrorism had not been ruled out, but urged patience until the investigation presents its results. …

“The plane was in excellent condition,” Smirnov told the news conference. “We rule out a technical fault and any mistake by the crew.”

Well, if it’s not the jet that failed, and if the crew didn’t make any mistakes — two assertions made without qualifiers by Smirnov, at least according to the news report — then the cause had to come from somewhere. Three other possibilities exist. One, someone on board had a bomb big enough to blow the plane apart, which would be somewhat puzzling considering that this was a charter for a tour group returning to Russia. Two, someone sabotaged the plane before it took off, although this scenario appears to still require a bomb.

Or two, ISIS may not have been just exploiting a tragedy for some cheap PR. James Clapper told reporters this morning that while no evidence of the capability for an ISIS attack at 31,000 feet has been uncovered, he’s not exactly saying it’s impossible either:

James Clapper, the U.S. director of national intelligence, says he could not rule out that the Russian passenger plane which crashed in the Sinai was brought down by Islamic State extremists.

Clapper told reporters in Washington that “we don’t have any direct evidence of any terrorist involvement yet” in the crash Saturday that killed all 224 people on the Metrojet.

But he noted that the Islamic State group, which has claimed responsibility, has a significant presence in Egypt’s Sinai Peninsula. Asked if Islamic State extremists had the capabilities to bring down a passenger jet, he said, “It’s unlikely, but I wouldn’t rule it out.”

The AP quotes a French aviation expert who suspects a bomb or other sabotage, based on Smirnov’s comments. If so, that doesn’t rule out ISIS involvement — in fact, it might make it more likely. On the other hand, the head of Russia’s aviation agency criticized Smirnov for those comments, calling them speculative at best until all of the fragments of the airliner can be reassembled and analyzed. Five nations will provide investigators to check the flight data and the remains of the jet, including Egypt, Russia, France, Germany, and Ireland, where the plane was registered.

For now, no one can be sure what exactly happened to the Metrojet flight, but perhaps Smirnov should take a hint from his flight agency in Moscow. Nothing can be gained by getting out ahead of the evidence, except for those in ISIS who may be exploiting this tragedy to spread even more irrational fear.