Four people were shot to death today inside a St. Louis health-care business in a murder-suicide, the Post-Dispatch reports. Two men and two women were found dead inside the building, and police say the male shooter is among the victims. Surveillance video shows the shooter having a brief argument with the other three before pulling out a semiautomatic handgun, reports Fox2Now. Police think the shooter is one of the Somali owners of the business, AK Home Health Care, but they don't know what the dispute was about. The victims were believed to be in their 40s and 50s.