More suspicious devices addressed to prominent Democrats — to New Jersey Sen. Cory Booker, California Sen. Kamala Harris and another to former intelligence chief James Clapper — were being investigated by law enforcement officials Friday.
The device addressed to Booker was intercepted in South Florida. The FBI confirmed that a suspicious package addressed to Booker had been recovered, adding that it was "similar in appearance" to at least 10 other packages this week addressed to high-profile Democrats and media figures.
Booker's office did not immediately respond to CNBC's requests for comment.
Separately, the New York Police Department said it removed a suspicious package from a U.S. Postal Service branch in midtown Manhattan that was "consistent" with the other suspected explosives. NBC News reported that the package was addressed to Clapper, who was the director of national intelligence during the Obama administration.
Later Friday morning, a man was arrested in Florida in connection with the ongoing investigation and is expected to face federal criminal charges, according to NBC News.
After the arrest of Florida resident Cesar Sayoc, 56, law enforcement officials told NBC that a similar package addressed to Harris was intercepted at a Sacramento postal facility.
White House press secretary Sarah Huckabee Sanders told reporters that "the president is receiving constant information as it is available." President Donald Trump, in a tweet Friday morning, said it was "very unfortunate" that the "'Bomb' stuff" has slowed the GOP's voting momentum ahead of the November midterm elections.
The White House did not immediately respond to CNBC's inquiries about the president's tweet.
Packages sent in manila envelopes and containing potentially explosive material have been addressed to former president Barack Obama, the New York residence of former president Bill Clinton and former Secretary of State Hillary Clinton, the New York office of news network CNN and actor Robert De Niro, among others.
De Niro, in a statement, said: "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!"