If it's done wrong... careful planning and good observation could make all the difference-
Someone should be installing a multi-camera system with night vision right now.
Then with a secure web feed, and a conference call, we could have someone watching each camera... all feeding info to a team on-site.
OK, I went all high-tech- but I'm a network engineer, what did you expect?
oh, and I almost forgot- don't rely on the site internet (cable, dsl, etc), put in a router with 3G+ wireless backup (yeah, I know it could be jammed- but then you'd immediately go to high alert)