What is the origin of the grudge between neighbors?
As for who was responsible for most of the killings, I believe it was local police and captains, as well as paramilitaries, and their subordinates. When a conflict like this breaks out between former neighbors, especially those who may have had grudges from the past, the bloodshed can be awful. Most Westerners try to see this through the lens of WWII history, where German soldiers and SS under political command perpetrate crimes. That is completely the wrong way to look at this because the mentality of the people is very different, very individualistic, very tending towards factiousness and rebellion.