Police said the threat was received at the Time Warner building at 25 Columbus Circle Thursday night.
CNN said several fire alarm bells signaling an evacuation rang inside its newsroom shortly after 10:30 p.m.
In a tweet, CNN's Brian Stelter said the office had been evacuated and that CNN was airing taped programming.
In October, the building was partially evacuated after a suspicious package containing a crude pipe bomb was delivered to the company.
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