So I found some pics of the losee center where the shots came from. In one pic, I noticed a ladder and it got me wondering if there are other ladders around the building that the shooter could have accessed to get to the roof.
I also noticed on a map that the losee center is built into an embankment. Notice the two cars parked on the bottom left. I wonder if it's possible the shooter accessed the roof from that vicinity. Maybe used a box truck and climbed to the top to get to the roof?
No inside access/badges needed. He just got up top from the outside.
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