I live in Vegas, haven't heard anything...
Her source is a Doctor, who is a Board Member of the Hospital.
The NSA & FBI rolled into town yesterday and ordered a city wide Disaster Drill, which did occur for those who are part of the drill. My wife did receive her drill call but my father-in-law answered the call and thus it was not communicated to my wife. My wife went into the hospital at her regular 5:00am time and found out about this alert.
All police, fire, EMT personnel leaves are cancelled.
According to this Doctor, all Doctors are supposed to be on standby and not leave town.
As of this moment, the hospital itself has NOT communicated the alert status to the rest of its staff.
I have no idea if this is just rumors built upon rumors at this point.