Weird police cars/activity. Any one else see this?

Today I was driving to my parents' house around 5:45/6:00. I was sitting on Riverside Drive in traffic waiting to turn on to Johnson Ferry to go north to East Cobb. Traffic always backs up there for about a mile or so. From somewhere behind me, I heard sirens, and about 5 silver cars of random makes/models came around the corner behind me on the wrong side of the road with lights flashing and sirens blaring. The lights were all inside the cars like an under cover car might have. The cars were all different makes including Honda and Toyota and mostly sedans but a couple of SUV's and trucks. One even had an out of state license plate.

They proceeded into the intersection and acted all disorganized line they didn't know which way to go. The front two cars almost hit eachother and the back truck hopped the curb. Then they proceeded doubt on Johnson ferry as if heading back to sandy springs.

My fiancée also saw this and he said he saw something similar on 285 last week.

Anyone have any idea what is going on? It seemed really sketchy to me.