The man accused of assaulting and kidnapping his 78-year-old grandmother is now accused of killing her, according to police. But by Sunday afternoon, the woman’s body had not been found.

Divers searched a pond at Chapel Hill Park in DeKalb County for signs of Millicent Williams, reported missing one week ago. Her grandson, Gregory Anthonyh Williams, has been charged with her murder.

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ALSO: Grandson charged with kidnapping, assault

Gregory Williams, 36, had been in jail since Thursday, when he was found in his grandmother’s car. He was arrested in a Kroger parking lot and charged with kidnapping, aggravated assault and theft by taking. On Saturday, he was charged with felony murder, though her body was not located.

Family members reported Millicent Williams missing Sunday, according to DeKalb police. Officers found her Decatur-area home in disarray and there was blood inside.

Police and court records showed Millicent Williams had previously feared her grandson would hurt her. Her grandson, an Army veteran with mental illness, had even threatened to kill her, according to a police report.

Gregory Williams lived for several years with his grandmother in her Brookgreen Point home. But during a three-year period, officers were called six times to the home following disputes between the two, police reports showed.

In August 2014, Millicent Williams called police when her grandson got mad at her for not giving him money to buy cigarettes.

“Miss Williams stated the suspect became irate and started yelling, calling her derogatory names and approached her in an aggressive manner,” the report states. “She stated the suspect approached her and gestured as if he was going to strike her.”

Gregory Williams enlisted in the Army in November 1999 and was a petroleum lab specialist at Fort Bragg in North Carolina, according to a military spokeswoman. Williams served until 2002, earning a national defense service medal, Army service ribbon, and parachutist badge. Though his grandmother believed he’d served in Iraq, Gregory Williams was never deployed, the Army said Friday.

Gregory Williams was being held without bond late Saturday at the DeKalb jail. His next court hearing is scheduled for Aug. 15.

Millicent Williams was last seen by her family Sunday.