The FBI said via its Twitter account that the recovered package was "similar in appearance" to those sent by 56-year-old Cesar Sayoc, whom authorities accuse of sending explosive material to Democrats and other prominent critics of President Donald Trump.
CNN President Jeff Zucker says all mail to CNN has been screened offsite since last week, when a series of package bombs began appearing around the country. Among them were two apparent mail bombs sent to CNN.
Sayoc was scheduled to appear Monday in federal court in Miami. He is accused of sending bubble-wrapped manila envelopes to Democrats such as Barack Obama, Hillary Clinton and Joe Biden. The packages were intercepted from Delaware to California. At least some listed a return address of U.S. Debbie Wasserman Schultz, former chair of the Democratic National Committee.
She represents the Florida district where the former male stripper, pizza driver and strip club DJ lived in an older van covered with bumper stickers praising Trump, disparaging Democrats and CNN and showing rifle crosshairs over liberals like Clinton and filmmaker Michael Moore.
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Although authorities did not immediately say who might be responsible for the most recent package to CNN, the FBI said it believes the package discovered Monday is "similar in appearance" to those that Sayoc is accused of sending. Law enforcement officials have said they believe the packages were staggered and more could be discovered.
Separately, a U.S. official told The Associated Press that Sayoc kept a list of elected officials and others who investigators believe were intended targets. The official also said authorities recovered soldering equipment, a printer, and stamps similar to those used on the package bombs.
The official wasn't authorized to discuss an ongoing investigation and spoke on condition of anonymity to the AP.
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Sayoc was arrested Friday outside a South Florida auto parts store after investigators said they identified him through fingerprint and DNA evidence. He is being prosecuted in New York, so his Florida hearing will likely be brief and process-oriented. The main issue will be whether he waives extradition to New York and whether he seeks release on bail.
Authorities say Sayoc faces more than 50 years in prison if convicted on all charges. None of the bombs exploded and no one was injured.