Explosions at the Boston Marathon, potentially ricin-laced letters intercepted en route to the White House and Sen. Roger Wicker, and an explosion at a fertilizer plant in Texas have each prompted investigations. In each case, authorities sift through evidence to construct a timeline of events.
Investigating Explosions And Chemical Threats
By editor • Apr 18, 2013
Originally published on April 18, 2013 1:44 pm