I was playing with my bro. and I was holding a knife in my hands and he see on his monitor that I am holding I pistol (FNX) which I had in my inventory. I raised knife and have attacked with knife I saw animation how I haul off with knife, but he saw me like I am shooting and he also can hear gun shot which I do not hear. I also tried to place another things to my hands but he still saw me holding a pistol.
Reconnecting to server helped.