BOROUGH PARK, N.Y. (WABC) -- The apartment building explosion in Brooklyn that killed two people and injured three others may have been intentional, officials said Tuesday.
The explosion happened Saturday in a three-story building on 13th Avenue near 42nd Street in the Borough Park section of the city.
Officials initially pointed to natural gas from a stove as the possible cause of the explosion, but they're now looking at the potential of another fuel source. In fact, law enforcement officials confirmed there was no natural gas in the apartment where the explosion happened.
Investigators were back at the site Tuesday to try to zero in on the type of fuel used. Officials removed two stoves from the building as part of their investigation.
Surveillance video of the blast is perhaps the first big clue that this wasn't a typical gas-feed explosion. The video shows a simultaneous blast and fireball blowing out of the second floor of the apartment of 48-year-old Francisca Figueroa.
When comparing it to the deadly gas-leak explosion in the East Village last March, there's a huge blast but initially no fireball. Minutes later, the gas-filled building turned into a burning inferno. In Saturday's blast, there was the initial fireball but few flames afterward.
Investigators now believe that's because there was probably no gas leak to feed a fire. The investigation is now focused on the intentional setting off of the explosion. Debris is being tested for any chemicals that may have been used as an accelerant. While all possibilities are being looked at, there is now renewed interest in Figueroa's financial debt, which we are told was considerable.
She was being evicted from her apartment for being months behind on rent and her gas had been turned off back in June. Just prior to the explosion on Saturday afternoon, the mother of three and hairdresser had texted her children with what one source described as farewell messages. But Figueroa's sister told Eyewitness News that she "does not know whether she was in debt." But she insisted that her "sister did not commit suicide."
Figueroa's body was located in the rubble Monday.
A neighbor, Ligia Puello, 64, was found in the hallway on the day of the explosion and pronounced dead at the scene from severe burns.
Debris also struck two men and a 9-year-old who were walking on the sidewalk at the time. They are expected to survive.
Five buildings have been vacated, and two of them are expected to be demolished.
Stay with abc7NY for the latest on this developing story.