RIVERVIEW, Mo. (AP) — A man charged with murder in August in St. Louis County is dead following another shooting. The St. Louis Post-Dispatch reports that 21-year-old Demarcus Pierce was found by Riverview police Friday morning. He died Saturday at a hospital. St. Louis County police took over the investigation and are trying to determine if there is a link to a fatal shooting in August in Wellston. Pierce and another man were both charged with second-degree murder in the death of Babacar Dia. Dia was killed when shots were fired into a car.