Police say a 77-year-old man was shot and Grant Prestonkilled by his 34-year-old grandson on Sunday evening in Lithonia, Georgia, about 20 miles east of Atlanta.

Lithonia Police, in a news release, said that officers responded to reports of a possible shooting around 6 p.m. on Sunday.

Authorities arrived at the scene to find the "lifeless body" of the man, police said.

An initial investigation was conducted into the incident and the deceased man's 34-year-old grandson, Jamal Nicholl, was identified as the suspect and arrested.

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'Truly heartbreaking event'

The Lithonia Police Department released a statement saying in part, "This is a truly heartbreaking event, and our thoughts are with the affected loved ones during this difficult time."

The police said that the motive behind the action is unknown at this time and that the department "remains dedicated to conducting a thorough investigation into the tragic event."

The police did not specify if any charges have been filed against the suspect.

While the police did not reveal further details on the victim, his stepson told FOX 5 Atlanta that his stepfather was a Vietnam veteran who had dementia.

The Lithonia Police could not immediately be reached for an update on the incident.

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Saman Shafiq is a trending news reporter for USA TODAY. Reach her at [email protected] and follow her on X, the platform formerly known as Twitter @saman_shafiq7.