Fire officials have not yet released a suspected cause of the blaze, adding that no member of the Trump family was in the building at the time.
“This was a very difficult fire. As you can imagine, the apartment is quite large, we are 50 stories up. The rest of the building had a considerable amount of smoke,” Fire Commissioner Daniel Nigro said on Twitter.
President Trump, who has an office and a private residence in the midtown Manhattan structure, was not in the building at the time.
“Fire at Trump Tower is out. Very confined (well built building). ... ” Trump tweeted.
Asked whether that assessment was accurate, Nigro said, “It’s a well-built building. The upper floors, the residence floors, are not sprinklered.”
Fire sprinklers were not required in New York City high-rises when Trump Tower was completed in 1983.
Subsequent updates to the building code required commercial skyscrapers to install the sprinklers retroactively, but owners of older residential high-rises are not required to install sprinklers unless the building undergoes major renovations.
About 200 fire personnel responded to the incident, which the department called a four-alarm fire.
Video on social media showed flames outside of a few windows and black smoke billowing up from the high-rise.
In January, three people were injured in an early-morning fire at the top of Trump Tower. One firefighter was hospitalized while two people received minor injuries that were treated at the scene, the New York Fire Department said.