(CNN) Police and CNN have issued an all-clear message after the network's New York offices and studios were evacuated Thursday night because of a phoned-in bomb threat. 
 
 "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. 
 
 Read More
– CNN says its New York offices and studios have been given the all-clear after a bomb threat was phoned in Thursday night. The threat at Manhattan's Time Warner Center forced the evacuation of the facility and the closure of part of West 58th Street to vehicle and pedestrian traffic, the New York Post reports. Police say a man with a southern accent called CNN at around 10pm and said five bombs had been placed in the building, reports the AP. Fire alarm bells rang in the newsroom and Don Lemon's CNN Tonight, which had been on a commercial break, ceased broadcasting as the network switched to taped programming. After around 30 minutes, Lemon and Brian Stelter resumed broadcasting from outside the building. "We were told to evacuate the building and to do it as soon as possible," Lemon told viewers. "We grabbed what we could and got out of the building and now, we are standing outside of the building." After the all-clear was given, CNN Worldwide President Jeff Zucker thanked authorities for the swift action and praised the "patience and professionalism" of staff. (CNN had to evacuate the facility after a suspicious device was found in October.)