There are a lot of these shootings, as well as dozens of strange deaths of individuals and plane crashes, etc. and they have similar clues and methods. Then there are the really big ones like JFK, 911, Benghazi, the USSN Liberty, and so on. The big ones are hidden like crazy not just because of the high-level US criminality, because foreign services are often employed, for example the Israelis in the sinking of the USS Liberty and the killing of American sailors. In the current situation the CIA used MI6 to conduct illegal ops against Trump, so it is tough even for Trump to go full disclosure. But if things don't improve with the UK Deep State, Trump will have nothing to lose.  Screw 'em, they tried to overthrow Trump and our country.