My Two Male Cats are Fighting Constantly

Question
Karen,

I live in a house with five cats (3 females, 2 males).  Two of the females don't leave on room of the house, so they're not much of a problem.  The other 3 are indoor-outdoor cats.  Two cats we found wandering the streets, one wandered up to our house and we kept him, one was from a rescue, the other from a friend.  The issue is our two males, the one who wandered up & one of the two we found in the streets.  The one we found in the street (Chambers) is my cat-he follows me everywhere, comes when I call him, we play tag and Hide-n-Go seek, and when I come home after long absenses (school or church) he waits for me outside and comes running up to my car.  The other (Bosanova - Nova for short) is really just a wanderer.  He comes home to eat and sometimes he'll stay inside and sleep on the couch.  At times he disappears for a while but he'll show up.  But we love him no less.  When Nova first joined the family, he and Chambers were the best of friends.  They were inseperable, they'd sleep together, play together-but never hurt each other.
A short while ago, Chambers developed a more...aggressive way of playing.  He'd attack the unsuspecting Nova, stalking him whenever he's around and then he'd just pounce and chase him around the house until somebody grabbed a hold of one of them.  Chambers has been getting worse and worse weekly.  It's worrying all of us and giving our other cat (Dominque - a.k.a Nikki) a heart attack and 'poofy tail'.  What's weird is that this behavior sprung up out of no where.  Chambers didn't go to a vet, Nova didn't go to a vet.  Chambers just decided to play a game of "Cat-and-Mouse" with Nova and now it's so bad-when, say, Nova is to come inside, we'd put Chambers out, let Nova eat, and when he goes back out, we bring Chambers in.  They're constantly fighting!  Just an hour ago Chambers attempted to disembowel Nova-and there was a handful of white fur all of the living room.
Do you know where this came from?  Or what we could possibly do to stop it?  Please help!

- The Allen Family

Answer
Hi Allen's,

The first question I have to ask is are they fixed? If not then this is the root of your problem. The males are asserting their breeding territories. This will get worse until you get them neutered. Write back and let me know if this is the case. Good luck.

Ciao, Karen