Bomb squads have been called to a post office in Atlanta about a suspicious parcel, just hours before a Florida man faces a court hearing accused of sending packages containing explosive material to prominent US Democrats.

The FBI did say who was meant to have received the most recent package, but CNN president Jeff Zucker announced that a suspicious package addressed to the cable television network was intercepted on Monday at an Atlanta post office.

Mr Zucker said there was no imminent danger to the CNN Centre. Another package was delivered to the cable network’s New York offices last week, causing an evacuation.

The latest suspicious package comes just hours before a federal court hearing was scheduled to begin for Cesar Sayoc, 56, who faces five federal charges.

Atlanta probe
A bomb squad arrives with other authorities at a mail facility in Atlanta (AP)

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 Debbie Wasserman Schultz, the former chair of the Democratic National Committee.

She represents the Florida district where Sayoc, a former male stripper, pizza driver and strip club DJ, lived in a van covered with bumper stickers praising President Donald Trump, disparaging Democrats and CNN and showing rifle crosshairs superimposed over leading liberals such as Mrs Clinton and filmmaker Michael Moore.

Authorities did not immediately say who might be responsible for sending the most recent package sent to CNN, but law enforcement officials have said they believe the packages were staggered and that more could be discovered.

The network said that the “package looks similar in appearance to the wave of pipe bombs that were mailed last week to prominent Democrats around the country, including two that were addressed to CNN’s New York bureau”.

Sayoc was arrested outside a South Florida car parts store after investigators said they had identified him through fingerprint and DNA evidence.

He is being prosecuted in New York, so his Florida hearing is likely to 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.