Smoke could be seen coming from the Midtown building.
The building was not evacuated.
A firefighter suffered a minor injury when debris fell on him. An engineer also suffered some minor smoke inhalation but refused medical attention.
As of 8:30 a.m. Monday, there was still a heavy presence of emergency vehicles closing off the street in front of the building on Fifth Avenue.
There is no word yet on the cause of the fire.
The president's son Eric tweeted his thanks to firefighters for doing "an incredible job."
The Associated Press contributed to this post.