Fire investigators are trying to find out what caused an explosion and fire that burned a large detached garage at a Fort Wayne home yesterday.  A neighbor called 9-1-1 after hearing the blast just before 5 PM and and went to check on the residents of the house on Florence Avenue near State.  When firefighters got there, the home was engulfed in flames.  The fire department was able to quickly get the fire out.  No  injuries were reported as a result of that blast.