Sad about the tragedy, prayers for the victims and their families.

If you are still planning it, I suggest you do it yourself using the public transit(and depending on which sites you plan to visit, get a museumkard, will save you time at entrances of the sites).

But do give yourself sufficient time to get back. If you have access to the TK flagship lounge, it has (or had) its own security entrance which will save you time going back.