This is the 6239th most frequent Russian word.
убитыми
"Убитыми" means "killed" or "slain" (instrumental plural form).
Used as part of a participial phrase to describe a resulting state or condition.
Мы нашли их убитыми в лесу.
We found them killed in the forest.
Used as an adjective in instrumental case to describe the state resulting from the action.
Они были убитыми в бою.
They were killed in battle.
Illustrating the instrumental case used to describe a passive state observed by others.