Of course it was fake and on top of that poorly done.
I was also at work that day and on CNN in Europe they were playing a loop of plane crash into a building. Just before the "crash" the plane disappeared for a split second - bad animation. When I told someone, everyone yelled at me that I was a heartless piece of shit with no sense of reality...
Now it turns out that my sense of reality was much more developed than theirs 😂