I think I might have encountered a hacker while playing on XBL... [video inside]

So guys, I played a match today and I noticed one the opponent players was acting quite strangely.

The first time he killed me, I was running from the US Spawn to the bridge (where the E flag is located in PC Conquest) and he started shooting at me. I emptied a whole FAMAS mag directly at him and none of my bullets ever hit him, afterwards he came in front of me and although we were face to face, he assasinated me (At first I thought I was lagging, but actually I wasn't).

Later on, I noticed that also my teammates were unable to kill this guy by using their weapons, since the bullets just went throught him like he was a ghost and the only way to kill him is by throwing nades at his feet or by knife assasinations, while he was able to kill everybody with ease!

*Even more strangely, this guy has played 177 hours, has almost 7000 kills with the knife and still has a positive K/D Ratio.

**I've recorded him with my mobile phone and I made a youtube vid. Just see what he does and tell me if this is even possible without using any hacks (especially in the first clip where he runs to bunch of my teammates and he C4s them without even get hurt)

TL/DR: I've might have found a hacker playing bf3, see the vid and tell me your thoughts..