The bomb threat was called in while CNN's Don Lemon was in mid-broadcast.
CNN has been given the all clear to re-enter the building and are back on the air.
"The NYPD is investigating a bomb threat near CNN NYC's office at Columbus Circle", he said.
Fire alarm bells rang out through the building announcing it was being evacuated. The caller said there were as many as five bombs planted in the building, according to the anchor.
"Earlier tonight there was a bomb threat called into the CNN officer in NY".
American broadcast network, CNN's NY offices and studio were evacuated on Thursday following a bomb threat.
The New York Police Department cleared employees to return shortly before midnight.
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'We were told to evacuate the building and to do it as soon as possible.
A bomb squad was on standby outside the building as police officers search the offices, a law enforcement source said.
He said: "Fake news - enemy of the people". The network went to playing taped content instead of being live.
CNN was targeted amid a wave of pipe bombs sent to opponents of President Donald Trump. Prominent democrats, including ex-US President Barack Obama, Hillary Clinton, mega donor George Soros, former Attorney General Eric Holder received similar packages.
In October this year, the NY offices of CNN were evacuated after a suspicious device was discovered in the building's mailroom.
None of the devices detonated, and no one was injured.