A tweet from the New York City Fire Department says that the two workers are trapped on the 45th floor - one level short of the roof.
NBC New York reports that 60 fire officers are attending the scene.
More top news
Twelve people have been killed and three injured after a pick-up truck and a church minibus crashed head-on in Texas.
Revenge porn offenders who attempt to magnify their targets' humiliation will face the toughest penalties under new sentencing proposals.
A remarkably mild night with misty low cloud on the hills of Scotland, Wales and north-west England and further rain in places.