A definite improvement, Donald. Thumbs up.
I've always felt "have died" sounded too passive and random, like the soliders just ate a bad tin of beans one day and eventually succumbed to botulism. "Have been killed" implies an active agent, and some might start asking questions like "Who by?" and "What for?", seeing beyond fatality figures to grasp a broader, deeper, richer understanding.
At least, one dearly hopes so.