Firefighters responded shortly before 12.30am to the 17-story New York City Housing Authority building in the Bronx, where people were seen leaning out of windows calling for help as flames engulfed parts of the top floors, officials said.
Chief of Department John Esposito said firefighters were investigating reports of a gas odour on the 15th and 16th floors when the explosion occurred.
He said there was major structural damage to about a dozen apartments and fires in 10 apartments on the 16th and 17th floors.
Authorities did not immediately release information on the person who died.
Another person was critically injured, five had serious injuries and eight had minor injuries, officials said.
Officials said the building had been undergoing renovations and work on the natural gas system had been completed and inspected.
The cause of the explosion was under investigation.
"It's an incredible tragedy. We're sending all our thoughts to the families involved," Leila Bozorg, deputy mayor for housing and planning said at an early morning news conference.
More than 200 fire and emergency crews were at the scene, according to the fire department.
"There were injuries. It was a very, very difficult night on a very cold night, which caused even more difficulty," Fire Commissioner Lillian Bonsignore said.
Officials set up a reception centre at a school near the building and the American Red Cross was there to help provide housing and other needs.
About half a million New Yorkers live in aging buildings run by the city's housing authority, known as NYCHA, which is the largest in the United States.
Many of the properties date back to the 1940s, '50s and '60s.
In 2019, a federal monitor was appointed to address chronic problems like lead paint, mould and lack of heat.
When he wrapped his five-year term in 2024, the monitor, Bart Schwartz, noted that the overarching issue for residents remained the "poor physical state of NYCHA's buildings".
