The Austin Fire Department says it started around 3 a.m. from improperly discarded smoking material in an apartment at 901 West 9th Street, just a few blocks north of Whole Foods Market.
Austin Fire reports the sprinkler system kept it under control until they got there.
ATCEMS transported one person to the hospital for treatment of smoke inhalation.
In total, three people are displaced.
One apartment has fire and water damage; another has water damage.