The New York City Fire Department says it began just after 7:30 p.m. inside the Associated Supermarket located at 1440 Amsterdam Avenue.
Investigators believe it started in a laundromat that is housed in the same building.
People we spoke with said they heard loud pops before the building was completely engulfed.
“The bricks just started blowing up. And it was crazy. People like actually buy food here and stuff. They use the laundromat and stuff. And it was all blowing up one by one,” said one witness.
“The store was being occupied as we arrived. People were actually in the supermarket shopping. And we evacuated the building before it got as bad as it did,” said FDNY Deputy Chief Michael Falatico.
The city fire department says there were no injuries.