The fire began on a sub-roof located on the fifth floor of a new building on NYU Langone Medical Center's campus.
The building is the Kimmel Pavilion, which is under construction. The pavilion is expected to open in 2018, with construction beginning in 2013.
Roofing materials appear to be what caught fire, sources said.
Video shows flames shooting from the building:
Smoke from the fire could be seen for miles. Eyewitness News viewers posted photos showing the smoke from all over the city.
See photos here:
NYU moved patients from areas impacted by smoke to other areas within the hospital.
There are no injuries reported.
Here's a look at the aftermath of the fire:
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