How to tell the owners the tragic news?

Hi, I need some urgent advice please.

About 10 days ago I saw a beautiful cat get run over and took it to
emergency vet. The cat unfortunately died probably immediately. She had no
ID tags/microchip so we were unable to contact the owner, but I told the
local vets in case anyone enquires.

However, I went out tonight and found the posters about a lost cat and it is
the beautiful one I saw run over. I couldn;t bring myself to call the owners
with such news at 2am, so will call them tomorrow.

So, the question is, how do I tell the owners? They obviously loved this
cat, and will be gobsmecked when they hear the news. Do I tell them over the
phone or ask them to meet me locally(we seem to be in same neighborhood)
then tell them? Would that sound strange to them? I would also hate them to
think that I was the one to run her over, when I just tried to help. I know
I know I am being paranoid, but I hate to bring this people such pain. I
lost my QT the same way 5 years ago, and I know how I felt for years after.
I know I can;t make it any easier for the owners, I just don't want them to
get a heart attack or something.

What would you do? Please write ASAP, as I must call them tomorrow(later
today - it's now 5am here).

Thanks for any advice

Gee