DOUGLASVILLE, Georgia – A Pelham man is charged with murder in Georgia, accused of running over a woman he didn't know Wednesday in what police described as a horrific and bizarre case.

Dewey Calhoun Green, 23, was booked into the Douglas County Jail just before 7 p.m. Wednesday. He is charged with murder, aggravated assault and aggravated battery, jail records show. He is being held without bond.

Green is charged in the death of 53-year-old Janice Pitts, who was killed in front of her daughter and infant grandchild. Pitts was on her way to Lowe's, said Douglasville Police Chief Chris Womack, when she was killed.

Womack gave this account of what happened: Pitts was in the southbound turn lane on Highway 5 waiting to turn left onto Douglas Boulevard. Green was behind Pitts in the turn lane and then, for no apparent reason, rear-ended Pitts' vehicle.

He backed up and rear-ended her vehicle again, and then a third time. When Pitts got out of her vehicle to check for damage, Green used his vehicle to pin Pitts between her vehicle and his, and then backed over her.

Green continued on for a short distance and went up an embankment until his car came to a stop. Witnesses took the car keys from him, and detained him until police arrived on the scene.

Authorities said Pitts was pronounced dead just after 2:30 p.m. from massive blunt force trauma.

Womack said investigators have no idea why Green did what he did. There is no indication that he knew Pitts, and the chief said Green had just exited the interstate so he doesn't believe there was time for a road rage situation to develop.

He said they have obtained a search warrant to get blood samples from Green to proceed with toxicology testing. It's unclear, Womack said, whether he was having some kind of medical issue or was under the influence of something. "Obviously we believe this young man wasn't in the right frame of mind,'' Womack said.

Womack said Green told them he was on his way to Atlanta to visit his girlfriend. He didn't provide any other details.

Alabama court records show he has had several traffic issues in Alabama, including a reckless driving conviction in 2011 when he was clocked driving 99 mph as he passed a vehicle in the median on Interstate 85 in Montgomery County. He is an extreme sports and photography enthusiast.

The chief said the investigation is ongoing, and described the incident as senseless.

"It's horrific,'' the chief said. "This lady was going to Lowe's. This could have happened to me, you, anybody.

"We encourage all citizens to be aware of their surroundings,'' Womack said. "There are some mean people and you can get hurt that quick. She was just taken out."