@msolga,
Hard to explain to the kids, hard to understand and explain to yourself. Just be honest and yourself and the kids will listen to you.
Sending you the strength to deal with this the best you and and to support your colleagues and vice versa.
Terribly terribly sad for this to happen in your small community.
We had an awful incidence many years ago in the UK Olga
http://en.wikipedia.org/wiki/Dunblane_massacre
Not to bring up the past, I think this shocked our world here... there may be advice or perhaps a number/contact/HT contact who may be able to help advise.
(Let me know if you would like to me to make enquiries in how they dealt with this- I can contact the HT there... all siutations are different but the basics in counselling these children and yourselves/colleagues may be useful).
My heart goes out to you hun ((((((((((((((Olga))))))))))))))))))))
Let others help you too Olga, dealing with kids is so very difficult. Hope you get some very good advice. I am SURE that the children who you talk to will benefit enormously for the skills, understanding and compassion we know that you have.
Take very good care xxxxx