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.
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A chilly start into tomorrow morning
A gas cylinder exploded in the Spanish coastal town of Velez-Malaga.
The car Mark Ross was travelling in was towed by police, but a kind police officer went out of his way to drive him to be with his family.