As a level four I had the same team twice in three weeks, with the same assessor (as they were called at the time) watching on both occasions - I know, bad planning! The first time I had four away team players off - although I actually missed the most serious incident in the game so it should have been five reds for one team.
A home player was fouled and the GK shouted at me "F***ing hell Ref! are you going to deal with that!" I looked at him and shouted at him to be quiet, then looked back at the player on the ground. In the half second I was looking away one of the two players standing over him had stamped on him leaving 6 stud marks on his chest. Neither my assistants nor the assessor saw which of the players it was so I had to deal as best I could, which wasn't ideal.
One of the spectators on that occasion wrote a match report about another game by the away team and referenced this one, saying it "bordered on downright thuggery!" I thought it actually went way beyond the border.
The next game I had 7 off, including 6 from the home team! The league had a bit of an issue with discipline!