NBC New York reports that the two workers have been secured using ropes, and emergency workers are trying to find a way of winching them to safety.
Parts of the streets below, on 57th and 58th streets and Eighth Avenue, have been closed off.
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Through the day we'll see plenty of sunny spells but there will be a risk of showers too as they filter down from the northwest.
Pilots say they are rostered in 'illegally' and feel fatigued from working too many hours.
The alleged hacking follows reports of similar attacks on other Democratic organisations, amid fears of state-sponsored hacking.