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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A woman thought to be travelling to Syria with four children has appeared in court charged with child abduction.
This afternoon it'll gradually brighten up across many parts of the UK.
Thirty US military cadets have been injured during an annual mass pillow fight by freshmen.