I understand that you don't want to have a single placemark equal 10 or so deaths
but how about a single icon with 10 or so smaller images(Crescent moon and star---equivelent of christian crosses I think) within the placemark it's self? you can size the placemark accordingly. The bubble could include number of people, date, what happend, ect as I'm sure you wouldn't be able to come up with names and such.

This was my first thought but it is way too flowery!
But It gets the idea across I think.



BTW, I hope I didn't do anything to offend anyone with this image! I know little about the Muslim religion.

It is meant to honor and respect!