At least some of the devices found in the wave of suspected pipe bombs mailed to prominent political and media figures had no possibility of exploding — because they contained flaws in the way they were made, several investigators told NBC News on Thursday, based on early analysis
.In a few cases, the flaws were substantial, the investigators said. In others, the defects were more subtle. But there's still no way to know at this point whether these deficiencies were intentional — to make convincing hoaxes — or simply the result of bad design or construction, the sources said.
The investigation's analysis is far from complete as some devices have yet to be analyzed at all in any kind of detail.
And officials continued to caution that anyone who gets one of these packages should treat it as dangerous.
Pressed at a news conference on Thursday afternoon as to whether the devices were supposed to go off or not, NYPD Commissioner James P. O'Neill would only say, "We are treating them as suspected explosive devices."
Law enforcement officials close to the investigation told NBC News on Wednesday that the bombs were made from PVC pipe with a digital timer attached to set off the detonator. Each bomb also contained powder from either a low explosive or a pyrotechnic, as in fireworks, they said.X-rays showed there were likely pieces of shrapnel inside of the PVC pipes, the officials said.
The list of mail bombing targets grew on Thursday to include outspoken anti-Trump actor Robert De Niro and former Vice President Joe Biden, as well as former Secretary of State Hillary Clinton, former President Barack Obama, former CIA Director John Brennan, billionaire George Soros, former Attorney General Eric Holder, Rep. Maxine Waters, D-Calif.
The device sent to Brennan was addressed to the CNN offices in New York City — despite the fact that he now works as a national security analyst for NBC News —prompting an hourslong evacuation of the building.
All of the packages were intercepted before reaching their intended targets.
A similar device was found in Soros' mailbox Monday. The FBI has sent the devices to its laboratory in Quantico, Virginia, for analysis.
Two senior law enforcement officials, and another official briefed on the investigation, said they are looking into whether some of the packages were mailed from Florida.
MSNBC senior law enforcement analyst Bill Bratton, who led police departments in Boston, New York and Los Angeles, told MSNBC earlier Thursday the FBI now has a number of devices they are going to be "in a position to dissemble to determine their functionality."
"Were they ever intended to actually function and if so how in terms of how were they supposed to be detonated?" he said."If not, well then that changes the focus from trying to cause bodily harm to effectively creating fear," he noted.
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Bratton said there had been some discussion about a "timing device" on the explosives, which raised further questions for investigators."These things are being found over the space of several days so what was the timer set for with no guarantee when it would in fact be opened or where it would be at any given time?" he said.
Bratton added that the sheer number of devices intercepted is actually a help to the investigators."The building back of the investigation is going to be assisted tremendously by the fact that there are so many of these things, 10 of them," he added. "And there's the potential for a slip-up."