NEW YORK — Authorities have now found two packages addressed to former Vice President Joe Biden and another to actor and Trump critic Robert De Niro that are similar in appearance and contain potential explosive devices that resemble the others sent earlier this week to prominent critics of President Donald Trump and CNN, a law enforcement official said Thursday.
FBI and local authorities are responding to two scenes at Delaware post offices, which Delaware State Police said were in Wilmington and New Castle. Earlier Thursday, a suspicious package addressed to actor-director Robert De Niro was reported at the Manhattan building where his production company is based, and its marking and contents appear similar to the other pipe bomb packages, two law enforcement sources said.
The FBI said Thursday morning that the three packages are "similar in appearance to the others."
A manhunt is underway for the perpetrator behind the packages. Law enforcement authorities are treating the series of bombs as a domestic terror matter and are advising the public to remain vigilant.
The motive is unknown, but the recipients are all prominent targets of right-wing criticism and, in many cases, of Trump himself. The package found at CNN's New York bureau in the Time Warner Center was addressed to former CIA Director John Brennan, city and local law enforcement officials said.
Devices sent to former President Barack Obama, Hillary Clinton, former Attorney General Eric Holder, California Democratic Rep. Maxine Waters and Democratic donor George Soros showed the presence of a sulfur substance, which could have exploded, a law enforcement official said.
The devices are believed to be pipe bombs, inherently unstable, and at risk of being set off just by handling.
The FBI's counterterrorism division is leading the investigation Thursday into the packages and the agency says it's possible additional packages were mailed to other locations.
At the White House, Trump vowed Wednesday that "we will spare no resources or expense" to pursue the perpetrator.
De Niro is a vocal critic of Trump.
The package sent to the actor also had the same return address as the others: that of Democratic US Rep. Debbie Wasserman Schultz of Florida, the sources said. There is no information to suggest she sent the packages.
And, just as the other packages, the one sent to De Niro had six American-flag stamps arrayed in two rows. No postmark is visible on the front of the De Niro package, similar to some of the others, the sources said.
None of the bombs in the other packages detonated, and no one was injured.
Before this package was reported, authorities said seven pipe bombs stashed in manila envelopes were discovered this week addressed to six prominent Trump critics: Former President Barack Obama; former Secretary of State Hillary Clinton; former Attorney General Eric Holder; Democratic US Rep. Maxine Waters (one to her California office and one to her office in Washington); former CIA director John Brennan (sent to CNN's New York offices); and billionaire investor and Democratic donor George Soros.
Authorities also are trying to track down a package believed addressed to former Vice President Joe Biden, two law enforcement sources told CNN's Josh Campbell and Brynn Gingras on Wednesday night. The package, considered suspicious because of its similarities to the others, was misaddressed and returned to the sender; US Postal inspectors are working to locate the package.
On Thursday morning, law enforcement officials said they believe they've found the Biden package. Details weren't immediately available. FBI Public Affairs Specialist Dave Fitz told CNN agents were "responding with our law enforcement partners to a US Postal facility in Delaware."
Building is open after evacuation
Tribeca Enterprises co-founder Jane Rosenthal said Thursday that the building was evacuated after the package was found, but that it has been re-opened.
"The building is open and everybody is safe," she told CNN. "This is not what free speech should look like."
De Niro's criticism of Trump
At June's Tony Awards, De Niro went off-script while introducing a performance by Bruce Springsteen to curse Trump.
"First, I wanna say, 'f**k Trump,'" De Niro said. "It's no longer 'Down with Trump,' it's 'f**k Trump.'"
Trump responded to the comments in a series of tweets, calling De Niro "a very low IQ individual."
It wasn't the first time De Niro had spoken out against the President.
In January, his speech at the National Board of Review Annual Awards Gala included a profanity-laced rant directed at Trump.
"Our baby-in-chief -- the j***-off-in-chief, I call him -- has put the press under siege, ridiculing it and trying to discredit it through outrageous attacks and lies," De Niro said. ""This f***ing idiot is the President. It's 'The Emperor's New Clothes' -- the guy is a f***ing fool ... our baby-in-chief -- the 'J******-in-chief' I call him."