Received Homophobic, Threats, and Racism from Summoner

I played a game and i know that summoners are pretty evil at night in ranked but... not this much a summoner that played well in a game started to flame everyone in the game for every mistake i ended up blocking him but before i even blocked him the things he said were extremely threatening to all the players on our team. Once the game ended i added the guy and wanted to apologize for my poor playing (5/9/8 khazix not all so bad) and when i was apologizing what i received was this...(Ill send images of texts from my image file for who contacts me) and even now this guy is still spamming me somehow even after i deleted him.