Capital: The threat, which was based on a single source and was uncorroborated, also mentioned Washington DC as a potential target

The bomb squad and a unit specializing in chemical and biological threats will sweep hotels, theaters, construction sites and parking garages.

Bomb-sniffing dogs and radiation detectors will also be employed.

Backpacks and large bags have been barred from the area. All other bags will be searched and metal detectors will be used to screen everyone in the crowd.

Chief of Counterterrorism James Water said: 'We are very confident that New Year's Eve in New York City will be the safest place in the world to be'.

Commissioner Bratton noted that authorities were ‘not aware of any threat that we deem credible to New Year's Eve celebrations in NYC.’

But he added: 'The ability to protect everything all the time everywhere is not possible in any venue anywhere in the world.'