"We heard this huge explosion and we heard this guy just come running and knocking on all of our windows doors saying, 'Wake up! Your house is on fire,'" said nearby resident Deborah Jessup.
Nearly 100 firefighters were met by a wall of flames that grew more intense, whipped by the wind.
David Flores snapped one of the first images of the fire.
"I was up doing some work and smelled the smoke and that's when I looked out the window, saw it and called 911," said Flores.
Thanks in part to firewalls, crews managed to keep the major damage confined to the two-story town home. The bad news, they say, is that the top floor entirely collapsed, leaving two to three feet of rubble.
"It's not survivable in the unit that was involved," said Fire Chief Mike Casey with the Houston Fire Department. "That worries everybody, us too."
A family member told firefighters she drove the 60-year-old man who lived in the unit home Monday night. It's the last time anyone heard from him.
"Firefighting is a science. They are going to take their time. They have to think about the safety of the individual involved and whether or not they can get to that individual based on magnitude of the fire," said HFD Spokesperson Pat Trahan.
Arson investigators are on the scene. The cause of the fire is still under investigation.