[GrenadeMagnet]

Ya, welcome to the god-mode mulitplayer cheat. Read some of the other threads here and you'll see more details. 2015 is working on a fix.

I was on a server earlier and ran into an Allied guy who was also in God mode. What's even better is that some players can instead give themselves back health, meaning it's hard to tell if they are cheating unless you watch their stats while playing.