Nice day today with bad weather ahead, so I decided to make my last hive inspection before winter. Removed the honey super and set aside - some honey stored there. Top deep looked good - surprised by the amount of capped brood and larvae - removed to the side. Bottom deep very light, some pollen... Then I turned and looked at the super and top deep and saw them crawling with bees. Took me a moment to realize what was going on - an enormous robbing disaster in progress! Tops of the boxes were so thick with bees I had a hard time putting the hive back together. Of course, I was shutting up the robber bees inside my hive.
Put a wet sheet over the hive, but it was pandemonium - a cloud of confused bees, bees fighting everywhere.
Distracted myself by making a robber screen per Michael Bush's book. At dusk I will uncover the hive, assuming that any bees left are my own foragers waiting to get in, and then I'll put on the screen and hope for the best tomorrow - supposed to be rainy the next few days.
When can I safely start feeding them to make up for the damage? Fortunately, I have a gallon of their own honey from extraction.