Officials intercept packages sent to top Democrats as police respond to device found where CNN New York office is based.
Police have given the all clear after a phoned-in bomb threat forced the evacuation at the offices of Cable News Network TV news channel in New York.
The police said a man with a southern accent called the CNN just after 10pm local time on Thursday (3am GMT on Friday) and said five bombs had been placed throughout the facility inside the Time Warner building at Columbus Circle.
Police said the building was evacuated and building security did a preliminary search. Police units then swept the building with the NYPD bomb squad on standby.
Nothing suspicious was found, CNN later reported.
Outside the building, CNN’s Brian Stelter and Don Lemon continued to broadcast. Lemon said fire alarms rang and a loudspeaker told them they needed to evacuate during his live show.
Lemon said he was in the middle of preparations for his show when the order to evacuate was issued.
All vehicle and pedestrian traffic around the CNN offices had also been blocked by police, said New York Police Detective Hubert Reyes.
In October, the building was partially evacuated after a suspicious package containing a crude pipe bomb was delivered to the company, addressed to former CIA Director John Brennan.