We let our tabby/calico mix cat, Callie, go outside during the day because she enjoyed being outdoors and also to get away from our other cat who persisted on bullying and tormenting her. One afternoon when she was out I happened to walk outside just in time to see a stray pit bull chase and grab her and shake her around like a rag doll until she died.
Oh my god. That is horrifying.
Yes, it was so heartbreaking. I had to call my husband who came home from work so we could bury her in the back yard. He was heartbroken, too, because he and Callie had a special bond.
I rescue animals, it's best not to let cats wander outside. So many bad things could happen.
We definitely learned our lesson, but the silver lining is that she didn't appear to suffer. Looked like the dog broke her neck and she probably died instantly. And at least she was doing what made her happy right up until the last. That's great you rescue animals. Do you foster them and find homes for them?
yes! That can happen around any bigger dog. We had a foster dog do it. It is horrible! So sorry for your loss. I have lost many this past year. Accidents happen. 
It's always sad but there is little you can do other than keep them indoors where they are miserable. I'm sure I'm not the only one to suffer this kind of loss.
You are not! I let my cats outside but supervised. Yes it's hard if they love it. You can get a special cat fence :) 