According to the Aurora Fire Department, fire fighters were dispatched to the 1300 blk. of E. Indian Trl. at around 1:09 p.m.
Upon arrival, fire crews found a wood frame multi-unit assisted living apartment building with nothing showing from the exterior.
Further investigation found moderate smoke in the common hallway of the building.
The smoke was discovered to be coming from an end unit where a sprinkler head had activated and extinguished a fire that started in the living area.
Staff members attempted to put the fire out, but were unsuccessful.
All residents were able to evacuate when they heard the fire alarm; no injuries were reported to civilians or to fire fighters.
The cause of the fire is under investigation at this time.
Officials say the unit where the fire occurred sustained minor damage and is still habitable.