NEW YORK — Investigators say some of the package bombs targeting critics of President Donald Trump were sent through the U.S. Postal Service, but that no new ones have been found in the mail system the last eight hours.
A U.S. Postal Inspection Service spokesman said Thursday that postal employees and inspectors are searching mail facilities for packages matching the 10 sent over the last four days.
A New York City Police commissioner said officials are treating the devices as if they’re real and harmful.
FBI Assistant Director William Sweeney said during a press conference Thursday, “Any device could be considered potentially dangerous and treated as such until proven otherwise.”
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.”
None of the devices so far in this week’s scare have detonated. Investigators are still trying to piece together where the packages came from and how they reached their respective destinations.
Sweeney also said during the presser, “I’m not going to get into specifically where we think the packages came from. Some were obviously delivered or were in the postal system. I’ll leave it at that. Other than that I’m not going to get a description of where we think the packages originated.”
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 characteristics, including excessive postage, homemade labels and high-profile addressees, security experts said. The parcels also contained a number of misspellings.
The U.S. 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.”
The Inspection Service says on its website that it has investigated “an average of 16 mail bombs over the last few years” while processing more than 170 billion pieces of mail. “That means during the last few years, the chances that a piece of mail actually contains a bomb average far less than one in 10 billion!”
The Postal Service does not have the resources to X-ray every parcel and typically reserves that technology for packages postal inspectors deem suspicious.
While the Postal Service intercepted some of the packages in this week’s scare, the developments underscored the limitations of the screening technology in use, said Phil Nater, a former longtime postal inspector in New York.
“There’s a lot of human activity involved before mail actually goes through a screening device or system,” Nater said. “It’s gotten a lot better, but it’s not impossible to bypass.”
However, the Postal Service has successfully intercepted a number of suspicious letters and packages in recent years.