Dietz worked on the Washington sniper case as well as the "Unabomber" mail-bomb case.

CNN: L.A. manhunt reminiscent of D.C. sniper case

Suspicious parcels, reported bomb threats and seemingly odd pieces of mail prompted evacuations and emergency alerts from Washington to Arizona to Michigan.

WSJ: Obama Attends Boston Service as Officials Probe Videos

Army bomb experts were called to examine the package, which had been taken from the Royal Mail sorting office.

BBC: Neil Lennon bomb police probe fifth suspect package