Law enforcement officials aren't sure whether they've discovered the last of the pipe bombs mailed to prominent Democrats and other opponents of President Donald Trump.
"This morning, another suspicious package addressed to CNN was intercepted at an Atlanta post office".
The official also said authorities have been scrutinizing Sayoc's social media posts.
Authorities have said the previous packages contained possible bombs made of six inches of PVC pipe, a small clock, a battery, wiring and what authorities termed "energetic", or possibly explosive, material. The official wasn't authorized to discuss the ongoing investigation and spoke on condition of anonymity to the AP.
CNN President Jeff Zucker sent a memo to staffers in which he assured them that "t$3 here is no imminent danger to the CNN Center".
President Jeff Zucker said the package posed no danger to the channel in the incident that came just three days after the arrest of a man accused of sending several mail bombs to prominent individuals last week.
Spokesman Kevin Rowson said via email that the agency had been notified by the U.S. Postal Inspection Service of a suspicious package that arrived at 400 Pryor Street in downtown Atlanta, which is the address of a post office.More news: Suspect arrested over 12 bombs, suspicious packages sent to Trump critics
Sayoc, shackled at the wrists and ankles and wearing a tan jail jumpsuit, said little at the hearing but at one point tearing up.
In this undated photo released by the Broward County Sheriff's office, mail bomb suspect Cesar Sayoc is seen in a booking photo in Miami.
Sayoc faced five federal crimes and could serve half a decade in prison.
One of Sayoc's attorneys, Daniel Aaronson, urged people not to rush to judgment based on media reports.
"We don't know what they have yet". Sayoc was arrested Friday in Florida after investigators said they linked him to the packages through fingerprint and DNA evidence.
Balsamo reported from Washington.
A suspicious package was reportedly mailed to CNN's office in Atlanta and intercepted on October 29, the network stated.
On Friday, FBI Director Christopher Wray said there is strong evidence linking Mr. Sayoc to the bombings that terrorized the nation.