Hacker.

Server: DayZ Livonia EU - DE 4313 (Persistence ON) IP: 195.82.158.113:11500
Time: Around 15:05 GMT +2
My steam profile: https://steamcommunity.com/profiles/76561198011310973
Incident: Encountered a cheater. We couldn't see him (invisible), me and my friend just suddenly took damage at our base. First my friend lost half of his hp, then I got killed and 1-3sec after my friend got killed too.