You have, in effect, incurred two debts with one act.
Sometimes the place of death will subordinate their claim on you to the place of citizenship but if you show up in their area later they will want a piece of you.
People don't tend to like murder.
“When you kill a citizen of one place in a second place both places can take a whack at you. “
Does that mean that if I kill one of those folks who entered the US without benefit of proper procedure (shall we say), the deceased’s home country can “take a whack” at me?