The fire occurred in the 800 block of Andover Road at about 6:15 a.m.
Neighbors said home security video may have captured the moments before the blaze started.
The video recorded a series of popping sounds followed by white smoke rising from the area, according to neighbors. Not long afterward, flames appeared and spread through all four homes in the building.
Neighbor Bean Parra said the fire escalated rapidly.
"In like three minutes' time, it went from a really slow burn to something enormous," Parra said.
Parra said she was awakened by what sounded like an explosion.
"I woke up from a big explosion like a force," she said. "I went to go open the window and my mom screamed, 'There's a fire, we've got to get out of the house,'" Parra added.
When firefighters arrived, there were reports of people trapped inside. Authorities said a man who lived in one of the homes died in the fire.
Neighbor Hannah Harris said the fire was a reminder of how quickly a tragedy can happen.
"It's scary because we were just saying it could be a neighbor's house. It could be your house. You could be sleeping, and something like that happens," Harris said.
Parra described the victim as a neighbor, an older man and a veteran.
"Would walk around, talk to everybody, mow people's lawns. We would get Christmas cards," Parra said.
Firefighters from several companies worked to bring the blaze under control, a process that took about an hour and a half.
Investigators are examining the cause of the fire. The four-unit building has been roped off, and a restoration expert told Action News that the structure will likely need to be demolished.
Authorities have not released the victim's name as they continue to notify next of kin.
"It's sad that he passed this way," Parra said.
At least four families have been displaced by the fire, and the Red Cross is assisting those affected.
Neighbors are also encouraging members of the community to help the families who lost their homes.