Almost from the moment that EgyptAir 804 silently disappeared from radar this morning on its way from Paris to Cairo, the assumption has been that some sort of attack destroyed the plane. Earlier this afternoon, NBC News heard from US intelligence sources that they have data that strongly suggests an explosion. But what caused the explosion, if indeed one occurred? That question will take more time to answer:

Scoop: NBC News reporting that US intel sees evidence of explosion on Egypt Air MS804

— Ken Dilanian (@KenDilanianNBC) May 19, 2016

According to a senior U.S. Intelligence official, the cause of the crash is still unknown, but there’s a strong indication that an explosion occurred based on data called “phenomenology,” or Infrared and Multispectral imagers.

“It’s not conclusive, but it’s suggestive,” an administration official concurred. “Now, the question is, if there was an explosion, what caused it? Mechanical failure? Explosives? No idea at this point.”

There’s a “persistent stare” on the region, meaning the U.S. is currently collecting everything from sound waves through multispectral images to pressure.

CNN also noted the likelihood of a bomb in its report on the discovery of the plane’s wreckage:

Earlier today, Donald Trump tweeted that the plane’s disappearance was an act of terrorism, which drew a rebuke from former Defense Secretary Robert Gates on MSNBC’s Morning Joe. “Well, the things that you learn fairly early when you have responsibility is how often the initial reports or information you get on a situation prove to be inaccurate,” Gates told Mika Brzezinski. “And with the demands of news media and so on, there’s always pressure to immediately react before you know really what’s going on.  And that’s a discipline a lot of politicians frankly don’t have.  At least until they have responsibility.”

Maybe Gates should have a word with Hillary Clinton, then:

Hillary Clinton on #EgyptAir: "It does appear that it was an act of terrorism" https://t.co/6OZtrfIwim https://t.co/ylixkSAdTJ

— CNN Politics (@CNNPolitics) May 19, 2016

Bear in mind that we know just about as much now as we did when Trump tweeted out his declaration. Terrorism appears to be the likeliest explanation now as it did this morning since Airbuses are not known to explode on their own, and any other crisis would usually give the pilots time to communicate an emergency. But if it’s an issue for Trump to assume that, then it should also be an issue for Hillary as well. (To be fair: Gates probably would apply that criticism equally if asked.)

The plane had 66 people on board, including crew and “security personnel.” We’ll have more as developments warrant.