At least seven people have died after a fire broke out in an apartment building in the Milwaukee suburbs Friday morning. A criminal investigation has since been opened by the Hartland Police Department. The source of the fire and the ages of the victims have yet to be revealed. Fifteen fire departments and nine police departments assisted in putting out the fire and rescuing people from the four-family apartment building. The American Red Cross is helping three families displaced by the fire. “This is a tragic incident for the community and for the first responders involved,” Police Chief Torin J. Misko said. “We ask that the community respect the privacy of the families.”