SAN ANTONIO -- A house fire late Saturday night gutted a south side home, leaving investigators searching for a cause.

The single story, single-family house in the 500 block of Sunglo Drive caught fire shortly after 9:00 p.m., according to residents that live on the street. By the time firefighters knocked down the flames, the home was considered a total loss.

Sunday morning, Louis Wolff, who said the house has been in his family for 30 years, picked through the rubble.

"Nothing's left," he said. "It's beyond repair. I'm going to have to call the city to see what steps I have to take to get it torn down."

Wolff said he originally bought the home about 30 years ago, and later sold it to his mother and father-in-law, who later left it to his son. His son, he said, had been staying with him, while his estranged girlfriend lived in the house. Firefighters found the woman outside the home when they arrived. She was not injured.

Wolff said arson investigators are looking into how the fire started, but he said he thinks it was set intentionally.