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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More than 20 people are still unaccounted for after a huge blaze broke out at the 'rave cave' club night.
President Michel Temer arrived in Chapeco to oversee the remaining repatriation of victims of the Colombia plane crash.
Most parts will be dry this afternoon, although there are a few showers out to the western fringes of Britain.