UPDATE: Florida man in custody in connection with bomb packages sent to top Dems

An explosive "pipe-bomb" style device similar to those targeting Democratic politicians and activists critical of President Trump was sent to the Camden office of U.S. Sen. Cory Booker, D-N.J., NJ Advance Media has learned.

Booker has been both a frequent and vocal critic of Trump, as well as a putative 2020 Democratic challenger to replace him.

A pipe bomb addressed to U.S. Sen. Cory Booker's office in Camden at 2 Riverside Drive was intercepted in Florida. Police and federal authorities were at the Camden office building early Friday investigating.

The package containing the explosive device was intercepted at a South Florida U.S. Postal Service center mail sorting facility in Opa-locka, according to a source familiar with the investigation, which is on-going. The Opa-locka facility handles packages mailed from Broward, Miami-Dade and Monroe counties.

An FBI spokeswoman in Washington, D.C., confirmed that the explosive device addressed to Booker was intercepted in Florida, but declined to be more specific about the location.

The #FBI has confirmed an 11th package has been recovered in Florida, similar in appearance to the others, addressed to Sen. Cory Booker. — FBI (@FBI) October 26, 2018

Saddened and angered that an explosive device was sent to @CoryBooker’s office. @NJOHSP is working closely with federal, state, and local partners to monitor the situation and coordinate our response. Grateful to law enforcement for keeping us safe from these acts of terror. — Governor Phil Murphy (@GovMurphy) October 26, 2018

Frightening and sad to see my friend Cory has now been targeted by these package bombs - but I know he won’t be intimidated & he won’t step back from all the amazing work he’s doing. Thank you law enforcement for your diligence & to our free press for keeping us informed & alert. https://t.co/JrVFLuFzYO — Senator Bob Menendez (@SenatorMenendez) October 26, 2018

Booker spokeswoman Kristin Lynch declined comment.

Booker's office in Camden is located at 2 Riverside Drive, a high-rise office building that also includes the state Division of Taxation, the Delaware River Port Authority and PSE&G.

The building remained open, though police cars were parked out front and an officer with a search dog was at the scene. People who work at the building continued to come and go on Friday morning, and there was no evacuation.

Police had mostly left the scene after 10 a.m.

"There was never any threat to the building," said John Hanson, the chief executive officer of the Delaware River Port Authority. The DRPA also has offices inside the building.

"In an abundance of caution, parts of the building were checked out to verify that, in fact, there was no threat," he told reporters gathered at the scene Friday morning.

Camden County Police Chief Scott Thomson said there is no danger to residents of the city, and that his department worked with the Bureau of Alcohol, Tobacco, Firearms and Explosives to "methodically" sweep the building.

He said everything was going "smoothly," but noted the toll such threats can take on civilians.

"This impacts not just the individual being targeted, but the community at large," he told reporters.

Thomson also said Booker's staff was still working Friday in Camden despite the threat, answering phones and "staying dedicated to the constituency."

A suspicious package has also been found at a New York post office addressed to former Director of National Intelligence James Clapper. Clapper, a retired lieutenant general in the U.S. Air Force, earlier this week called the slew of mail bombs "domestic terrorism."

The one discovered at a Manhattan postal facility was addressed to Clapper c/o CNN. An earlier package had been sent to former Obama CIA Director John Brennan in care of CNN in New York.

Investigators were analyzing the innards of the crude devices to reveal whether they were intended to detonate or simply sow fear just before Election Day.

The packages sent to Booker and Clapper mark the 11th and 12th sent by the serial bomber.

Breaking: Federal Agents just arrived with explosive sniffing K-9 at New Jersey U.S. Senator Cory Booker’s Camden office after suspected bomb package addressed to this office intercepted in Florida @FOX29philly pic.twitter.com/fpIc4wWdsC — Steve Keeley (@KeeleyFox29) October 26, 2018

Investigators have been searching coast to coast for the culprit and motives behind the bizarre mail bomb plot aimed at critics of the president.

Three more devices were linked to the plot Thursday -- two addressed to former Vice President Joe Biden and one to actor Robert De Niro -- in an outbreak of politically loaded menace with little if any precedent. Authorities warned there might well be more.

Robert De Niro statement following package sent to his office: “I thank God no one's been hurt, and I thank the brave and resourceful security and law enforcement people for protecting us. There's something more powerful than bombs, and that's your vote. People MUST vote!” — Jake Tapper (@jaketapper) October 26, 2018

Law enforcement officials told The Associated Press that the devices, containing timers and batteries, were not rigged like booby-trapped package bombs that would explode upon opening. But they were uncertain whether the devices were poorly designed or never intended to cause physical harm.

The officials spoke on condition of anonymity because they were not authorized to discuss the ongoing investigation by name.

Homeland Security Secretary Kirstjen Nielsen, in an interview Thursday night with Fox News Channel, acknowledged that some of packages originated in Florida.

The targets have included former President Barack Obama, Hillary Clinton, CNN and Rep. Maxine Waters of California.

Trump claimed on Friday he was being blamed for the mail bombs addressed to his critics, complaining in a tweet sent before dawn: "Funny how lowly rated CNN, and others, can criticize me at will, even blaming me for the current spate of Bombs and ridiculously comparing this to September 11th and the Oklahoma City bombing, yet when I criticize them they go wild and scream, 'it's just not Presidential!'"

NJ Advance Media reporter Amanda Hoover and The Associated Press contributed to this report.