A New York City firefighter died and more than a dozen others were injured Tuesday morning when a suspected drug den exploded while authorities were responding to a report of a gas leak.

Officials identified the slain firefighter as Battalion Chief Michael Fahy, a 17-year veteran of the department and father of three children between the ages of 6 and 11.

"It's a very sad day for our city," Mayor Bill de Blasio said. "Tragedy has befallen a family, our fire department and our entire city."

Fahy was directing operations from the street after firefighters were called to investigate the strong smell of gas coming from a home in the Bronx's Kingsbridge neighborhood. Authorities evacuated one person from the home and both adjoining buildings.

The home exploded around 7:30 a.m., about an hour after firefighters arrived. A piece of the two-story building's roof struck Fahy in the head, killing him.

Fire Commissioner Daniel Nigro called Fahy a "brave man" who was considered a "rising star" in the ranks during an emotional news conference at Allen Hospital. Nigro worked closely with Fahy's father, who also worked as a fire chief.

"We lost a hero today and our members are all saddened," Nigro said.

Nigro, de Blasio and Police Commissioner James O'Neil were with Fahy's wife and parents after the firefighters death and "saw the unspeakable pain when they were told formally that they had lost Michael," de Blasio said.

"(It's) a reminder of the dangers that our first responders face everyday, the dangers that the men and women of the FDNY face and the bravery in which they do their job," he said.

More than a dozen other people were also injured, including six police officers, nine firefighters, two civilians and three employees of the Con Edison gas company, Nigro said.

Firefighters found a suspected drug lab after they were called around 6:30 a.m. to investigate a reported gas leak at a home in the Bronx, WNBC reported. Police were called, but the home exploded before they could investigate.

O'Neil said the building in question was known to police. Two weeks prior to the blast, officers got information that it was "a possible drug lab, a possible grow house" for marijuana, he said.

Photographs from the scene showed bricks, drywall and debris strewn across pavement and over the tops of two vehicles. The innards of the once two-story structure spilled onto the street. The second story of the home appeared to be destroyed.

Authorities went door to door to evacuate neighbors before the blast, a resident who identified himself only as Jorge told WCBS. He said he heard the explosion and "knew right away it was this."

Barbara Nardo, another resident in the neighborhood, told the news station that she was awakened by the sound of the blast.

"I thought maybe it was lightning that hit a car or something," she said.

Authorities continue to investigate the cause of the explosion.