Police and CNN have issued an all-clear message after the network's New York offices and studios were evacuated on Thursday night because of a phoned-in bomb threat, the network reported.

“The NYPD has now given us the all clear, and employees have been permitted to return to the building,” CNN Worldwide president Jeff Zucker said in an internal memo to staff. “The building is secure and safe for everyone to return in the morning.”

“We appreciate the swift action by the local authorities, and the patience and professionalism of all the employees who were impacted.”

The threat was not substantiated, the New York Police Department tweeted.

The threat came Thursday night when a caller indicated there were five devices in the building, according to a law enforcement source. Several fire alarm bells rang inside CNN’s New York newsroom, signalling an evacuation after the call was received shortly before 10 p.m., the company’s security said.

Staffers evacuated the CNN New York offices in the Time Warner Center building and Don Lemon’s “CNN Tonight,” which had been on a commercial break, was taken off the air.

The network temporarily went to taped programming for about half hour before going live from the street while police investigated.

That package was among more than a dozen improvised explosive devices sent to prominent Democratic politicians and donors around the country in October.

None of the devices detonated, and no one was injured.

Suspect Cesar Sayoc, 56, was charged with five federal crimes and is currently in custody waiting for trial. If convicted, he could receive up to 48 years in prison.  

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