I was in my office when - on 9/11. I think I had a number of meetings scheduled. I was just getting to know the bureau. And somebody walked in and said the first plane had - or a plane had struck the World Trade Center, one of the towers.

I didn't know the organization, but the one thing you can say about the FBI, it's tremendously professional.

And at that point, I think we all realized it was something tremendously tragic, probably a terrorist attack, and the next step was to go down to our command center and get things going.

Robert Mueller Quotes