Five cars, a tractor-trailer and a box truck were involved in the separate incidents that happened just after 1 p.m., Marietta Police spokeswoman Jennifer Murphy said.
As of 2 p.m., Murphy said the center lane was open and wreckers were on the scene.
It was unclear whether one wreck triggered the other, Murphy said.
Traffic was delayed as far south as Delk Road, according to the Georgia Department of Transportation.
