It was a gruesome crime and police offered no clues as to why it happened. A California couple made a surprise trip to see their 5-year-old child who lived with his grandmother in DeKalb County.

During that visit, Montrais Kenton Boyd allegedly cut his son’s throat, then buried the small boy’s body in the backyard, according to police. Boyd, 25, was charged with murder.

Police were called Wednesday night to the Lithonia-area home on Rocky Pine Drive where the boy lived, according to DeKalb police spokeswoman Shiera Campbell. The child’s name was Montrais Boyd Jr. and his cause of death was sharp blunt injuries to the neck, according to the DeKalb medical examiner.

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“It was very difficult,” Campbell said Thursday afternoon. “The uniformed officers who responded first to the scene, it affected them and it affected everyone that was on scene.”

It may not have been the first violent crime for Boyd, according to online court records. A man with the same name is also facing charges in Arizona following an incident in June when he allegedly was driving naked with a young boy in his car.

On June 18 at 8:17 a.m., an Arizona State trooper responded to a report a man in the median on I-17 near Flagstaff, according to the Arizona Department of Public Safety. A black BMW sedan was blocking a traffic lane, police said, and a man approached the trooper’s car.

“A nude man ran towards his patrol vehicle and began striking it with his fists multiple times,” the ADPS said in a press release. “Our trooper drove away from the enraged man and stopped in front of the sedan. While doing so, be observed a passenger inside of the BMW. The naked man then entered the BMW and began ramming our trooper’s patrol vehicle numerous times.”

The passenger was the man’s 4-year-old son, according to investigators. The naked man’s wife told police she and her husband were in town visiting family when they had a fight, and her husband had left her along the interstate and driven away, Fox 10 news in Phoenix reported.

The suspect then left the scene and drove the wrong way on I-17 for more than a mile before losing control of the BMW, traveling across the interstate and hitting a rock embankment and rolling over, according to police. The naked man and his son were treated at Flagstaff Medical Center for bruises and abrasions and released, the ADPS said. The trooper was also injured.

At the hospital, the boy was released to his mother. The suspect, identified as Montrais Boyd of California, was arrested and charged with aggravated assault with a dangerous instrument, felony endangerment, child abuse and criminal damage. He was booked into the Coconino County jail, where he was held until Sept. 12, according to the Sheriff’s Office.

The suspect in the Arizona case is scheduled for a case conference Monday, court records showed. A public defender could not confirm whether his defendant is the same man accused of murder in Georgia.

On Wednesday, a Montrais Boyd and his wife arrived in DeKalb County to visit their son, according to police. The couple also had an infant.

While the boy’s grandmother and mother were away from the home, Boyd allegedly killed the boy, police said. Other children in the home, believed to be the grandmother’s children, were not injured.

Boyd was expected to make his first court appearance Thursday evening.