The building was promptly evacuated, a spokesperson for the museum told NBC.
While there are no reports of any injuries, the extent of the damage is still unknown.
Witnesses, however, reported heavy smoke.
We just got evacuated from @AMNH Came down smoky stairs. Real fire.
— Susan Perkins (@NYCuratrix) December 12, 2014
OMG the @AMNH is on fire!! We were evacuated & it was crazy! #americanmuseumofnaturalhistorypic.twitter.com/VOJaqgF6ZL
— Margot G (@Margotjg) December 12, 2014
Of course the one day I want to visit the Museum of Natural History it catches on fire. pic.twitter.com/rIjetYzgz2
— Natalie (@natalielovestv) December 12, 2014
Eyewitness News, still covering the situation, shows smoke pouring out of the building's first floor.
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