From sources I read some years after the massacres a great deal of was due to the hatred between the local Indonesians and the ethnic Chinese who were seen as dominating too much of the economy. The Chinese didn't have a chance. Undoubtedly, most of the people murdered had no political clout. It was just an excuse for the head murderers in the gov. to kill a lot of Chinese. The movie "The Year Of Living Dangerously" was something about the killings.