Guests at the Budget Suites in northwest San Antonio were forced to evacuate the hotel because of a fire early Thursday morning.
The fire broke out around 3 a.m. at the hotel in the 7800 block of Fredricksburg Road.
Fire officials said no one was inside the room where the fire began, but it was shown as occupied.
Firefighters arrived on scene quickly, but credit the building's sprinkler system for dousing the flames. About 100 guests were evacuated, but later allowed to return.
The arson unit was called to investigate the cause. No one was injured and damage estimates were unknown.