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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May has implicitly admitted that her flagship manifesto pledge was not properly thought through.
American superbike racer Nicky Hayden has died - days after being involved in a serious bicycle collision with a car.
The songs played included The Brady Bunch theme song, followed by The Smiths' Suffer Little Children.