The Sac County Healthcare Coalition will conduct a mass casualty training exercise tomorrow (Friday) as part of the emergency preparedness program. Many emergency vehicles, including ambulances and police cars, will be used as a part of the training, so residents are asked to be reassured that this is only a test and not to crowd the area to ensure proper training is received. The exercise will occur around the East Sac Elementary School and Loring Hospital. Again, Loring Hospital wants Sac City residents to know that this is only for training purposes and no emergency is actually occurring.