Photos shared on social media by Stelter and others show police investigating the alleged threat near the Time Warner Center complex, where CNN's NY head office is housed.
Brian Stelter, a reporter for the network, said on Twitter that the offices were evacuated and that CNN went into taped programming.
The threat was not substantiated, the New York Police Department tweeted. The caller said five bombs had been planted in the building.
CNN anchor Don Lemon told his Twitter followers the studio had been evacuated in the middle of recording his show.
Several fire alarm bells rang inside CNN's NY newsroom, signaling an evacuation shortly after 10:30 p.m. "We grabbed what we could and got out of the building and now, we are standing outside of the building", Lemon said. Prominent democrats, including ex-US President Barack Obama, Hillary Clinton, mega donor George Soros, former Attorney General Eric Holder received similar packages.
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"NYPD is going through our building", Lemon said, pointing to police officers lined up down the block, about 100 feet from the entrance of the building.
'FAKE NEWS - THE ENEMY OF THE PEOPLE, ' Trump tweeted just after 10pm.
The suspect, Cesar Sayoc, of Florida, was arrested and indicted on more than 30 federal counts, including use of a weapon of mass destruction, and he faces up to life in prison if convicted.
In October, CNN's NY headquarters was evacuated after a package containing a crude pipe bomb, which was addressed to ex-Central Intelligence Agency (CIA) chief John Brennan, was found.