The wave of pipe bombs addressed to prominent Democrats has raised fresh questions about the ability of the U.S. Postal Service and private delivery companies to intercept explosives and other dangerous items.
Biohazard detection, X-rays and other technologies have had some notable successes in recent years, but officials warn that the sheer volume of mail makes it impossible to catch everything.
“The public should not have the impression that all of our mail is screened like going through security at the airport,” said David Chipman, a retired agent with the Bureau of Alcohol, Tobacco, Firearms and Explosives. “That’s not the case, and we know that from a string of cases.”
In the meantime, Phillip Bartlett of the U.S. Postal Inspection Service’s New York division said hundreds of thousands of postal employees were searching the system for any additional bombs.
While two packages addressed to former Vice President Joe Biden were intercepted at postal facilities in Delaware on Thursday, a pipe bomb addressed to former Attorney General Eric Holder made it so far into the mail stream that it was returned to its purported sender: the Florida office of Rep. Debbie Wasserman Schultz, whose name was on the return address.
Another crude bomb addressed to former CIA Director John Brennan at CNN went through the U.S. mail before a courier took it to the Time Warner Building, where the cable network has its New York offices, according to a law enforcement official who was not authorized to discuss the investigation and spoke on condition of anonymity.
“Most if not all of these packages were sent through the U.S. mail,” the official said.
Those deliveries occurred even though the packages had certain suspicious features, including excessive postage, homemade labels and high-profile addressees, security experts said. The parcels also contained a number of misspellings.
“These devices are the poster children of what a suspicious package looks like,” said Fred Burton, a former counterterrorism agent with the State Department who serves as chief security officer for Stratfor, a global private intelligence company.
The Postal Inspection Service, which investigates mail-related crimes, said in an email that in screening the mail, the agency relies on a “targeted strategy of specialized technology, screening protocols and employee training,” as well as “state-of-the-art equipment to include portable X-ray machines.”