A man escaped fast-moving flames at a home on the South Side early Wednesday morning thanks to his nephew, who pulled off the door, frame and all.

San Antonio firefighters responded to the fire around 3:30 a.m. at the home in the 1700 block of Socorro near Loop 410 and Highway 281 South.

Fire officials said the home was fully engulfed upon their arrival and flames spread from the house to a detached apartment.

"It spread due to the radiant heat. They were probably about 20 feet apart," said San Antonio fire Battalion Chief Brian Lee.

Arson investigators said the fire started in a water heater at the back of the house.

"I see it in the news all the time. It happens all the time all over the city. This time, it was a little closer to me," said Jose Hernandez.

Damages to both homes on the property were estimated at $50,000.