Police outside Atlanta are investigating after a bystander's video shows an officer beating a homeless woman inside a convenience store.

DeKalb County Police reopened their use of force investigation after local media broadcast video shows the officer striking 38-year-old Katie McCrary at least 10 times. At one point, she grabs his baton as the officer presses her to the floor with his knee in her back, and he repeatedly shouts "let it go or I'm a shoot you."

The police report says McCrary had pushed the officer, who was questioning her about begging customers for money at the store in Decatur, Georgia.

Police said McCrary was taken to a hospital after her June 4 arrest. She's charged with obstructing law enforcement and was served a criminal trespass warning.