I hope you get out to your car safely when you go home.
I remember when I was little, I used to go to work with my mom. She was a courier for a medical laboratory. There was some guy outside the building being wierd and they locked all the doors. That's about the closest I've come to anything like that. LOL This guy was homeless though...not armed, I don't think.
Hope they get him outta there and it gets resolved soon.
ETA: I guess they are just being precautious in regards to him being not in the building, but nearby.
