I have a bad feeling that this is going to be Islamic terror sabotage - it is the most plausible explanation.
As a practical matter, this should be investigated as a crime scene until there is enough evidence as to determine if this is an accident or not.
If it is, fine, the NTSB conducts the investigation. we get a report in about 18 months or so.
If evidence indicates it is a terrorist attack, then the FBI and intelligence community take the lead.
Unfortunately this will play into the election, one hopes that the investigation is straight forward. However given recent history, there will be a lot of pressure by the administration to frame this within a “narrative” as opposed letting the investigation play out before coming to a conclusion.
It is frankly sad that that thought is what comes to mind.