The location of 78-year-old Millicent Williams' body is still a mystery to DeKalb County police, about two weeks after she apparently died.

In a rare move, investigators have charged her grandson, Gregory Williams, with her death in spite of her missing remains. Arrest warrants issued in late July said the suspect killed his grandmother with a "Rambo-style" knife and told police he would reveal what he did with the body if they got him a lawyer; he now has a lawyer.

“He still refuses to speak,” Lt. Lonzy Robertson of the police department said Wednesday.

Daryl Queen, who is representing the suspect through the DeKalb public defender’s office, said he’s looking into his client’s mental state.

“It is a sad and tragic set of events. As has been previously reported by the family, Mr. Williams has a long history of mental illness, therefore we are addressing those issues at this time,” Queen said.

Court and police records suggest a troubled relationship between grandmother and grandson. She said he suffered from PTSD after service in the Army and refused to take his medicine.

Though his grandmother believed he'd served in Iraq, Gregory Williams was never deployed, the Army said.

While rare, murder convictions can come without a body. In April 2014, for instance, Craig Lester Thrift of Waycross was convicted of felony murder in the presumed death of his cousin and best friend nearly 23 years prior, though the remains were never found.

DeKalb police, who conducted large searches last month, believe Millicent Williams is dead because no one could survive losing the amount of blood found in her home off Flakes Mill Road and in her car.

The warrants allege Gregory Williams forced his way into his grandmother’s bedroom between July 23 and 27, attacked her and used her car to dispose of her body.

The grandson was found with the car days later at a Kroger. There was also a layer of CD cases, with some cracked from apparent pressure, the documents said.

Williams remains in jail without bond.

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