Shortly before 9:00 on Saturday (10/25) morning, Chicago Tower Ladder 14 was on Chicago Avenue and radioed that they had smoke in the area and asked if anyone had reported a fire. They stated that it looked like it could be an auto or a garage fire and that they were trying to track it down. They quickly came back to report that they had a building fire on Karlov. I arrived just after first companies. Turned out they had a pretty good worker in the rear of an occupied 2-flat. The residents were not home at the time.