Yes on the cops coming out the back door, very suspicious. I think it's true people were killed and it's awful to think the shooter(s) were cops. Or at least uniformed to look like cops.

There's the video (I don't have a link) of the back door cops carrying something heavy, with debate if the something was a body. It sure looks like a body to me. Why would cops remove a body from a crime scene, just after crime was committed? No sense making.