LANCASTER COUNTY – A Lancaster County shooting has claimed two lives. Police responded around 4:05 a.m. yesterday to the 300 block of Sun Hill Road in Penn Township. Upon arrival, officers discovered two adults, one male and one female, both deceased inside a home. Police say 71-year-old Mark Shepherd, his 63-year-old wife Diane, and extended family members were inside the home at the time of the incident. Family members awoke to a loud domestic-related argument between Mark and Diane occurring in a separate part of the residence. Multiple gunshots were heard and both Mark and Diane were found with fatal injuries. Investigators determined that Mark Shepherd fired multiple shots from a revolver handgun striking Diane, and then proceeded to take his own life with the same weapon. Northern Lancaster County Regional Police, Lancaster County Coroner’s Office, and the Lancaster County District Attorney’s Office are collectively investigating details associated with the case.