I was in Berezino near the train station where a player was speed hacking around me. He went to the yellow house with maroon doors where I found 4 other bodies. He was playing 'tag' with me, zipping into the house and onto the street every few mins or so. I rushed him to the top floor where he shut the door and I proceeded to kill him. His name is 'Zombie Bait.' Granted all of my encounters over the past couple of days have been speed hacking, I've been unable to collect their names fast enough. I even had a group of 4 surround my friend and I at NWAF where we killed 2 of them. We respawned in Berezino and the guy walked up to my friend and stated "I have your AUG from the airfield, you want it back?" We were streaming when this happened.

TLDR;
Zombie Bait is speed hacking for sure. I watched him go from field hospital to yellow house in a few milliseconds and he was also able to run into a wall and disappear to later appear behind me.