We are reading Watership Down which I have found has many very accurate descriptions of rabbit behavior. The book characters are mostly anthropomorphised rabbits. The head rabbit of the Efrafa warren, General Woundwort talks often about other rabbits he has killed.
Normally you don't think of rabbits with behavior that aggressive.
Blackavar is rabbit who tries to escape from Efrafa but is apprehended & mutilated. His ears are torn to shreds.
Yesterday I attended an event where a rabbit named Avari was attending (Petco Addoption event), in the picture below you can see his ears have mostly been chewed away, his eyelashes are gone, and his nose is injured. A few months ago he was rescued from a hoarding sitiuation much like Efrafa. ~70 rabbits were being held together in a small out building. He was mutilated by other rabbits.
We can see that rabbits will fight until mutilation occurs. Will they also fight each other to the death?
Note: The story of Avari is true. He is currently recoverd from his injuries and available for adoption