From the link above:
So I hung up the phone, immediately called my chief of staff, told him to get as many of my people as possible to the hospital immediately. I hung up, called Director Mueller and — with whom I’d been discussing this particular matter and had been a great help to me over that week — and told him what was happening. He said, I’ll meet you at the hospital right now.
(snip)
I went out in the hallway. Spoke to Director Mueller by phone. He was on his way. I handed the phone to the head of the security detail and Director Mueller instructed the FBI agents present not to allow me to be removed from the room under any circumstances. And I went back in the room.
Actually, the whole thing is worth reading. It reads like a Tom Clancy novel.