Ha, yeah, that happened to me once during an Alliance battle (aka Luxons vs Kurzicks) in Guild Wars - I was playing as my own axe-wielding warrior/elementalist build, where the only elementalist skill actually in play was the skill "Shock". What that does, for those who don't play Guild Wars, is inflict a nominal amount of damage on an opponent and simultaneously knock them down. If they're standing there fighting you, that's not the most useful thing in the world, but knockdowns also interrupt actions (like spells with long cast times), and if you're running away, getting knocked down stops that and lets the pursuer close the distance again.
Shock is a touch-range skill, which means to use it the caster has to get within melee range of the target. The way the mechanics work though, once you get close enough to start the animation of the skill, it no longer matters if your target has kept running and is now some ways away from you, it's still going to hit and knock you down (unless you have some other defense against it, which would have probably prevented me from targeting you with the skill in the first place). So from the perspective of a target, I appear to be running up behind them and then stopping briefly as they keep running, until they suddenly fall down. Most people know why of course, but this story is about a schmuck who didn't.
So I had been repeatedly killing this one Kurzick player all during a particular match, because whenever I headed in his direction he didn't have the good sense to get out of dodge, and one on one his build couldn't take me; by the time he would wise up and run the hell away, I'd have cast Shock, knocked him down, and proceeded to beat the crap out of him. When he did run away, for some silly reason he'd stop after a while and let me catch up to him, and the Shock/beat down would resume. I must have killed that guy 20 times at the least. My teammates thought this was greatly amusing.
After the match though I get a self-righteous PM about how he was totally reporting me for hacking because I was "throwing that spell at him" and I shouldn't be able to do that, and I was totally going to get banned. At that point I would have been happy to explain the mechanics of touch range skills to him, but he'd decided to put me on ignore shortly after making his ludicrous threats.
So I turned over the screenshots I took of the incident to my friendly alliance and let them decide how to best go about responding to that cowardly attack on my honor (my guess is he got a lot of messages suggesting he was a jerk, heh), and promptly went right back to not being even slightly worried about getting banned, because accusing me of hacking the game was ridiculous.