Brazilians take football rather seriously. It's not all wearing speedos, playing samba football on the beaches of Rio - in some places people literally kill each other over a leather round thing that you punt about with your mates.
Pio XII is apparently a real place and not a spaceship. In said township, during a game the referee had given a red card to one of the players. The player refused to leave the pitch and things got physical. After words and fists didn't work, the referee decided that stabbing the player was the best thing to do. The player tragically died on his way to hospital.
If you saw one of your players being fatally stabbed by a referee, you would be shocked, angry, disgusted and whatever other emotion you want to throw in. You probably wouldn't storm the field, stone the referee, decapitate him and stick his head on a spike in the middle of the field. This happened this year, not 2013 BC.
This story is fucking mental but I read it on the Guardian and not the Daily Mail so I'm assuming it's true. I love football, but my message to you kids is please don't kill each other over it. Just make fun of each other, that's the grown up thing to do - you massive jerks who support a team that I don't support.