What to Know Officials are investigating up to 10 explosive packages sent to high-profile Democrats and supporters in nearly a half-dozen states

All had a return address linking to a high-profile Democratic party member; at least one of them also had a white powder envelope

The flurry of incidents began less than 48 hours after a bomb was planted in mailbox at billionaire philanthropist Soros' NY home

UPDATE: Some Devices Flawed, Unable to Explode; Others Yet to Be Analyzed, Several Investigators Say



Investigators seized three more suspected package explosives -- two addressed to former Vice President Joe Biden in Delaware and one addressed to Robert De Niro in New York -- early Thursday, bringing the total number of confiscated devices sent to high-profile Democrats and others to 10 in 72 hours.

Multiple officials briefed on the investigation say there are no solid leads on a suspect as of Thursday afternoon. While there are no known devices still outstanding, they remain concerned there could be others still undiscovered.

13 Suspicious Package Incidents

Within five days, apparent explosive devices were detected in the mail addressed to Democratic politicians Barack Obama, Joe Biden, Hillary Clinton, Sen. Corey Booker and Rep. Maxine Waters; billionaire philanthropist George Soros; the New York City offices of CNN and others. No one was hurt and investigators are working to determine if the incidents are all linked, though many of the devices appeared similar.

Officials say they are looking into whether at least some of the packages were mailed from Florida. They also say the devices were poorly made and it is unclear if these were attempted hoaxes or simply a case of bad construction.

Ten have been seized in total since Monday, though most of the intercepts came Wednesday. Three more -- to Biden and De Niro -- came Thursday. News of the De Niro device broke first. That one was addressed to him and had been sent to a Greenwich Street building he owns that houses offices for Tribeca Films and Tribeca Grill. A building worker called police early Thursday because, after seeing Wednesday's news, he remembered seeing a similar package a day or so earlier. The device was safely removed from the property.

Less than two hours later, the FBI and local police swarmed a postal facility in Delaware in connection with the bombing investigation. Sources had said authorities suspected a similar device may have been addressed to Biden. Nothing was found at his house, but investigators apparently tracked it down in a New Castle postal facility, officials said. It was said to be akin to the others. About an hour later, a second package addressed to Biden was confiscated at a postal facility in Wilmington, Delaware. Details on that one weren't clear.

In Pictures: Pipe Bombs Addressed to Hillary Clinton, Obama, CNN, Others

The De Niro device and at least the first Biden package had the same stamps and return address (that of Florida congresswoman and ex-Democratic National Committee chairman Debbie Wasserman Schultz) as others reported on Wednesday.

Two senior law enforcement officials say they are looking into whether some of the packages were mailed from Florida. They are also looking into any past incidents involving Wasserman Schultz's office and if any of those incidents could be connected to these devices.

As of early Thursday, there have been 10 such packages. In addition to Biden and De Niro, two devices in separate packages were addressed to Rep. Maxine Waters of California; ones were also addressed to Hillary Clinton, former President Obama, ex-Attorney General Eric Holder and former CIA director John Brennan. The first in the series was a mailbox pipe bomb left at the Westchester County home of billionaire philanthropist George Soros.

None of the devices detonated and no one has been hurt. Authorities are examining the crude explosives and warning there could be more out there. NBC News obtained an X-ray photo of one of the bombs, which shows protruding wires that appeared to be connected to a cylindrical device.



According to sources, the explosive devices were made from PVC pipe and contained a timer (likely a digital alarm clock) to set off the detonator. The powder contained in the bombs comes from pyrotechnics. X-rays show there was likely shrapnel inside the PVC pipe, law enforcement officials say.

The seven confirmed package bombs sent to political figures had several things in common and the discoveries are spurring calls for lawmakers to turn down the political rhetoric. Ray Villeda reports.

Meanwhile, investigators examining the explosive devices are working to glean forensic clues to help identify who sent them, gathering fingerprints and DNA evidence while tracking the origin of the packages and the components used. While some have made note of the fact that the devices were not postmarked, multiple officials have said this was not uncommon, and that because of the soft packaging they could not go through automated sorting machines to have their postage canceled.

Former NYPD Commissioner Bill Bratton said on MSNBC Thursday that it's a plus the FBI has recovered so many of the package bombs. They will look into whether they were intended to function, how they were supposed to detonate and where the design came from. That could help find an online trail.



Larry Johnson, a former head of criminal investigations for the U.S. Secret Service who also served as a special agent in charge of the presidential protective detail, said it is highly likely that the person or people who built the bombs have been previously flagged by law enforcement.



If you have info that could assist the #FBI's investigation of suspicious packages, call 1-800-CALLFBI (225-5324) or use http://tips.fbi.gov.

Authorities say they responded to an address at the home of philanthropist George Soros after an object that appeared to be an explosive was found in a mailbox. Katherine Creag reports.

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