Hephzibah, GA --

Authorities say an east Georgia man has been charged with beating his 92-year-old grandmother to death.

Police say 21-year-old Theodore Cornell Lockett was arrested early Sunday morning on charges of aggravated assault, burglary and making terroristic threats in the death of Dorothy Lockwood. A murder charge was added when Lockwood died hours later at the Medical College of Georgia.

Police say Lockett broke into his grandmother's Hephzibah home late Saturday night and beat her repeatedly with a glass-top table and a microwave oven. Police say he called his mother and told her he'd killed his grandmother and was going to kill her.

Authorities say Lockett had lived with his grandmother until recently.