The blast happened just before noon at a building on South Highland Avenue.
Fire officials said it appears to be a major gas explosion. Video from the scene shows windows and doors that appear to have been blown out from the building and debris scattered around outside.
Officials are evacuating surrounding homes as a precaution.
In addition to local authorities, the FBI in New York says it is investigating.
We are looking to see if there is anything for us to look at, spokesman Jim Margolin said.
No other information is known at this time.
