Daniel Defense gun there. (DDM4). Semi-auto. I guess he modified it?
Bump fire stock modification.
One of the weapons (possibly two) were full auto though. Read that somewhere. Might have been the AK as those are easy to modify. He had one to fire at hotel security and lightly armed police.
Two officers were on his floor within 10 minutes. They held back and waited for SWAT to arrive - though every mass casualty training protocol course tells LEO to engage immediately. Took 72 minutes from start to finish. That’s forever.