— Everyone sent the explosive devices so far is a prominent critic of President Donald Trump, but no motive has been determined for the mail-bomb campaign and no suspects have been identified.
Former President Jimmy Carter has been warned by law enforcement that he could be a potential target and should be on alert for a potential pipe bomb sent by mail, his spokeswoman said.
Former Vice President Joe Biden and actor Robert De Niro are the latest high-profile figures to be sent explosive devices this week in a suspected mail-bomb campaign.
Everyone sent the explosive devices so far is a prominent critic of President Donald Trump, but investigators have not determined a motive nor identified any suspects.
Two were sent to Biden in Delaware in the latest of the series of 10 mail bombs and suspicious packages that law enforcement is responding to with a domestic terrorism investigation, sources told ABC News.
The FBI, Secret Service and the Bureau of Alcohol, Tobacco and Firearms (ATF) were fanning out across the country early Thursday to determine where components of the devices were purchased, which may give clues to who is responsible.
X-ray photographs of the devices exclusively obtained by ABC News illustrate the critical leads investigators are now pursuing: Each device contained a digital clock, explosive powder, a battery power source and wiring to channel a spark for detonation, sources told ABC News. The devices also included glass as potential shrapnel. None of the devices have exploded, but they had the potential to maim or kill.
The two packages to Biden were intercepted at different postal facilities Delaware.
The package addressed to De Niro was discovered at the actor’s Tribeca Productions film and television company in New York City early Thursday morning. It was removed by police in a bomb-containment vehicle.
Packages similar to those addressed to Biden and De Niro were sent to former Secretary of State Hillary Clinton, former President Barack Obama and CNN’s New York headquarters.
“The FBI advises the public to remain vigilant and not touch, move or handle any suspicious or unknown packages,” the FBI said in a statement Wednesday evening. “We ask anyone who may have information to contact the FBI.”
The series of mailed explosives began Monday with the discovery of a pipe bomb in the home mailbox of billionaire philanthropist George Soros in Westchester County, New York. Soros is a Democratic supporter often criticized by right-wing groups.
The following day, a package addressed to Hillary Clinton containing an explosive device was intercepted by the Secret Service at a screening facility before it reached her home in the suburb of Chappaqua, also in Westchester County. Former President Bill Clinton was home at the time the package was found.
Hillary Clinton, speaking at a campaign event Wednesday in Coral Gables, Florida, said, “We are fine, thanks to the men and women of the Secret Service who intercepted the package addressed to us long before it reached our home.”
“But it is a troubling time, isn’t it?” she added. “And it’s a time of deep divisions and we have to do everything we can to bring our country together.”
A package addressed to Former President Barack Obama containing an explosive device was intercepted by the Secret Service early Wednesday morning before it reached his residence in Washington, D.C.
Later that morning, a package containing an explosive and suspicious powder was found in the mail room of the Time Warner Center in Manhattan, which is home to CNN’s New York headquarters. It was addressed to former CIA director John Brennan, though he is a NBC News contributor and has no public ties to CNN.
The package addressed to Brennan traveled through the U.S. mail system, two officials briefed on the investigation told ABC News. It arrived at the Radio City post office where it was picked up per normal procedure by a private courier who delivers the mail to the CNN office and other locations, the officials said.
The courier then hand-delivered all of CNN’s mail for that day, including the manila envelope with U.S. Postal Service first-class mail Forever stamps, which feature the American flag. That’s how the package wound up in CNN’s screening and sorting mail room, the officials said.
There didn’t appear to be any postal markings on top of the stamps, which investigators are looking into.
A suspicious package was sent to former Attorney General Eric Holder with a return address for Democratic Rep. Debbie Wasserman Schultz in Florida. The package did not reach its intended destination and so was sent to the congresswoman’s address on Wednesday. Authorities do not believe Wasserman Schultz, former head of the Democratic National Committee, was involved in sending any of the packages.
Another package containing a device addressed to Democratic Rep. Maxine Waters of California was found in Los Angeles on Wednesday night. A prior one addressed to Waters was intercepted earlier Wednesday by Capitol Police in Washington, D.C.
The two packages sent to Biden and the one to De Niro brought the total under investigation to 10 on Thursday morning.
All packages were intercepted before reaching their intended targets. It’s not entirely clear whether all of the incidents are linked, but authorities said they feared other bombs may have been sent.
The packages, bubble-wrap-lined manila envelopes with computer-printed labels and Forever stamps, have been sent to the FBI’s lab in Quantico, Virginia, for further analysis. The devices found inside are also being examined for fingerprints and DNA.
Bryan Paarmann, special agent in charge of the FBI’s Counterterrorism Division and Joint Terrorism Task Force in New York City, said at a press conference Wednesday that the mailings appear to be political in nature.
“The utilization of violence in order to further one’s own political agenda is unacceptable to us,” Paarmann told reporters. “We will turn over every rock, we will turn every corner and we will talk to everybody that we have to in order to mitigate this threat.”
Trump on Wednesday night called for “peace and harmony” from a rally in Mosinee, Wisconsin, but added: “The media has a responsibility to set a civil tone and to stop the endless hostility and constant negative and oftentimes false attacks in stories.”
Also on Wednesday, from the White House, Trump said his administration is “extremely angry” about the incidents, adding that “the full weight of our government is being deployed to conduct this investigation and bring those responsible for these despicable acts to justice.”
Democratic leaders noted that most of the people targeted on Tuesday had been ridiculed by Trump.
“We listened with great interest to the president’s remarks this afternoon. We all take an oath to support and defend the Constitution and protect the American people, and that is our first responsibility. However, President Trump‘s words ring hollow until he reverses his statements that condone acts of violence,” Rep. Nancy Pelosi, the House minority leader, and Sen. Chuck, the Senate minority leader, said in a joint statement Wednesday afternoon.
“Time and time again, the president has condoned physical violence and divided Americans with his words and his actions: expressing support for the Congressman who body-slammed a reporter, the neo-Nazis who killed a young woman in Charlottesville, his supporters at rallies who get violent with protesters, dictators around the world who murder their own citizens, and referring to the free press as the enemy of the people.”
ABC News’ Karma Allen, Mark Crudele, Jack Date, Justin Doom, Julia Jacobo, Meghan Keneally, Mike Levine, Tara Palmeri, Pierre Thomas and Morgan Winsor contributed to this report.
