Fire crews rushed to a home on located at 3043 Grand Avenue South in Minneapolis on Tuesday after flames triggered an apparent explosion.
Sources within the Minneapolis Fire Department told FOX 9 News it sounded like a gas explosion caused the front porch area to collapse at about 4 p.m., and fire broke out shortly thereafter.
FOX 9's Maury Glover shared photos of the scene on Twitter. Follow him for more.
Witness Heidi Souza said she was driving by when she heard a large boom and hit the brakes. She said two passers by had just gone by the home, so she stopped to make sure everyone was OK.
"We just heard a loud boom. At first, it sounded like thunder to me," Chentu Berento, who was one of the pedestrians walking by, recalled.
Berento said she and her friend were nearly knocked off their feet. When they looked back, the women noticed the porch had been blown outward.
"The front part of the house came off," Berento said. "There was fire on a couple of pieces of cloth, so we went to see if anyone was in the house, anyone was hurt."
Wary of trying to enter, the witnesses called out to anyone who may have been inside.
"Tried calling out, but then a couple of minutes later, it started on fire," Souza said. "My heart is just pounding.
Upon arrival, firefighters found flames at the front of the structure on the first floor, where the porch had partially collapsed. The fire rapidly spread through the house and into the attic, and firefighters had to retreat from their first entry into the building because of the extreme conditions.
Flames could be seen pouring out of the windows as firefighters used hoses to suppress the fire when FOX 9 crews got to the scene. By 5 p.m., firefighters were entering the home to see if anyone had been inside at the time.
Firefighters then re-entered the building to completely extinguish the hot-spots inside, but the structure sustained extensive fire damage.
Neighbors told FOX 9 News the four-plex is occupied, but no one was home at the time of the explosion or fire. Firefighters say at least two dogs, and possibly a cat, were killed.
Roy Ayotte, one of the residents, said he lost everything in his apartment -- including his cat, Sammy, and 10 years' worth of graphic design work on his computer, which he uses to make a living.
"I collect action figures -- 40 bucks new, and they accrue value to $100 apiece. There were 50 of them. I guess I don't care as much about them as the cat," he lamented. "The cat was innocent."
One neighbor reported seeing a utility truck nearby a few hours prior to the blast. By 6 p.m., Mayor R.T. Rybak and representatives from CenterPoint Energy were at the scene.
The cause of the fire remains under investigation.