Hacks? Bug? Riot?

So.... i was met with something pretty weird in a recent ARAM game. We had the enemy team on the run, probably won the game at that point. Then the game froze for everyone except for the three people in a group on the enemy team. Could be a bug or a crash or something. All i know is that it seems pretty sketchy that the only people unaffected were in a group and that the replay also shows the freeze.