[Game Breaking] Global Game Froze for all Teammates

I was in the middle of a premade game with 3 other friends and 1 random. All of a sudden in the middle of the game, our clients all froze at the same time. I've never seen this happen before while playing this game. When I say our game froze, the time stopped moving, all effects in game stopped moving, we all had to either restart our computers or close league if applicable. I don't have a good computer so I had to restart my pc because I couldn't even alt tab out. When I loaded League of Legends back up, it said the game was over and we received a loss. We feel like we should not have earned a loss. What could possibly cause all of our games to freeze at the same time?