"I found the original source of the 16% figure and put that quote in the casualties section:

The Humanist article also reports: ""For over a decade the PA has violated Palestinian human rights and civil liberties by routinely killing civilians—including collaborators, demonstrators, journalists, and others—without charge or fair trial. Of the total number of Palestinian civilians killed during this period by both Israeli and Palestinian security forces, 16 percent were the victims of Palestinian security forces.""  

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