how my school handled it:
LMA Travel Advisory
Wednesday, January 31, 2007 – 4:00 PM
Improvised explosive devices have been found in several locations around Boston, Cambridge, and Somerville, during the day of January 31. So far all devices have turned out to be hoaxes. Law enforcement continues to search and investigate, and this will cause transit and traffic impacts throughout the evening commute. Please allow extra time. Media outlets are the best way to keep updated on the situation. There is no known specific threat at this time.