I think Colombians take up the top 3 or 4 spots on quantity though.
Between the top few, I think it was 3, they've killed something like 300+ people confirmed, and damn near a 1k "possible" victims. Most of them were street kids.
That's crazy.
Plus Colombia law will only give you 30 years max. And lots of time reduced for helping police and good behavior and stuff.
So 3 people, 1000 murders, if it started around the same time in say the late 60's early 70's they could all be out by now.