Are your rabbits neutered? Were they properly bonded or did you just put them together?
Rabbits need to be neutered and under go a proper bonding process before they can be caged together.
Needless to say, your two are going to need to be housed separately for a good while a least til the nethie is Heald and then you might be Able to attempt to rebond then following the steps outlined in the bonding section of this forum

Posted By Duchess on 7/29/2017 9:09 AM

I don’t know what to do. I need help!
I woke up yesterday morning to my mini bunny Duchess.( she hasn’t grown in a month sense we got her and she is the size of like a big apple.) screaming as my normal bunny Nestle, was chasing her around the cage and it seemed to hurt her! We checked her out saw no marks or bleeding. I looked up online that it could be bonding. So I left them alone and kept a eye on duchess and nestle. Not 10 min later it happens again and Nestle claws right under her eye and her back!
They have been cage mates for over a month. No problems no fighting. They always cuddled together and slept together. They are both female and what Nestle did had to require stitches in poor little duchess. I’m at a lost and have tried to figure out why Nestle attacked Duchess.

If you see your rabbits chasing and fighting one another, you cannot just leave them at it. That is not bonding. And you could end up with very injured bunnies, if not worse. You need to separate them immediately as Dface explained.

It’s very typical of not properly bonded rabbits to be the best of friends one moment and try to tear each other to pieces the next. You do need to separate them. Then both need to be desexed and healed before you attempt to bond them for real.

You definitely have to separate them immediately. It sounds like they might be young bunnies, which is why they were fine together at first, but now may be entering puberty. I’m assuming that they have not been spayed yet. It doesn’t matter if they are both female and if they were fine when housed together before. Maturing and puberty changes everything. You will end up with severe injuries or worse if you don’t separate them now. They can also come to hate each other and never want to be together if they fight and injure each other. Most vets will spay rabbits when they are 5 or 6 months old. Until then, they will have to be kept apart, not even let out to play and exercise together. After their spays and a few weeks have elapsed for them to heal and for their hormones to dissipate, you can start bonding sessions.

Here are 2 good articles on bonding:

http://rabbit.org/faq-bonding-multiple-rabbits/

https://binkybunny.com/BUNNYINFO/tabid/53/CategoryID/9/PID/940/Default.aspx

As the others said, separate immediately, spay, bond SLOWLY!! Do not keep them together!!