THE BRONX - Three firefighters suffered minor injuries battling a three-alarm fire at a Bronx apartment building.

The fire broke out at five-story apartment building at 2390 Hoffman St. It started as a two-alarm fire and quickly grew to three.

Tenants say they started to smell gas throughout the apartment building at around 10 a.m. Thursday, and heard a huge explosion at around 3:30 p.m. Flames then spread from the first floor up through the higher floors of the apartment building.

The apartment building's superintendent told News 12 that the fire started because of a gas leak in a first-floor apartment, and that the tenant of that apartment was not there at the time.

The deputy fire chief says the tenants will not be allowed back into the building. He also said the first, second and third floors suffered significant damage. While the fourth and fifth floors were not as affected, it's unclear if those tenants will be allowed back in because of smoke from the fire.

The Red Cross was on the scene, providing blankets and assistance to tenants.