Officials with major shipping companies says they have security measures in place to screen for dangerous materials, but they do not discuss them in order to maintain their effectiveness.
Kendall Daniel, U.S. Postal Inspector with the Houston Division, told KHOU in a statement, in part:
“The U.S. Postal Service has developed a comprehensive approach to protecting the mail system by utilizing a targeted strategy of specialized technology, screening protocols and employee training. The Postal Inspection Service has organized response teams nationwide for investigating suspicious parcels through our Dangerous Mail Investigations (DMI) Program. DMI Inspectors are trained to recognize the common characteristics of suspicious mail and are highly proficient in the use of state-of-the-art equipment to include portable X-ray machines.”
Daniel also writes, “In order to prevent attempts to compromise the effectiveness of our investigative methods, the U.S. Postal Inspection Service does not comment publicly on our investigative procedures and operational protocols.” The 2017 Annual Report from the Postal Inspection Service, the U.S. Post Office’s federal law enforcement agency, lists 19 cases initiated involving suspicious substances and items, including bombs and explosives, that resulted in 20 convictions or pretrial diversions.