DULUTH, MN (KDAL) - A fire in a first floor apartment at 823 East 1st Street in Duluth sent residents out into the cold early this morning.  Although the fire was mostly extinguished by the residents prior to the Fire Department's arrival, the building was filled with smoke and crews remained on the scene for about an hour.  At least four of the residents were taken to a hospital for smoke inhalation.  The cause of the fire is under investigation but is said to be suspicious.