Deputies have formally charged a South Carolina man suspected of being a serial killer with three additional counts of murder for bodies found buried on his land.

The arrest warrants issued Monday against Todd Kohlhepp were for killings that Spartanburg County Sheriff Chuck Wright already said the 45-year-old real estate agent was responsible for.

Wright says Kohlhepp has killed seven people in South Carolina, including four at motorcycle shop in 2003.

The arrest warrants issued Monday say Kohlhepp shot 25-year-old Meagan Coxie on Christmas or Dec. 26 after holding her against her will. Warrants say he killed her husband, 29-year-old Johnny Coxie the week before.

Arrest warrants also charge Kohlhepp with killing 32-year-old Charlie Carver. Kohlhepp was arrested Nov. 3 after deputies found Carver's girlfriend chained in a storage container.