13 minus 11.... Q and A

Thirteen bobbies enter the pub (including the police sergeant), but we see only eleven convicts in uniform (including Dr Twist, posing as the police sergeant) coming out of the door. What happened of the remaining cops?

They are with their colleagues inside of the pub, but knocked out cold and still in uniform. (Bound and gagged? Quite likely, but that's not entirely clear) To catch a quick and somewhat indistinct glimpse of those fallen heroes, you must check the short scene with the police sergeant in his underwear contorting on the floor : they're lying in the background, right behind him.