This paper presents the slingstone assemblages recovered from two large-scale excavations at the Late Pottery Neolithic/Early Chalcolithic (c. 5800–4500 cal BCE) sites of ‘En Ẓippori and ‘En Esur. Based on contextual, morphometric and other archaeological data, we suggest that during this time, the slings and slingstones were used as weapons. The high number of slingstones found within the settlements, and the traits of systematic production they reflect (formalization, standardization and time-consuming manufacturing), point to an organized production of weapons, interpreted as an escalation in the preparations for war, alluding to the possible existence of local power centers in the region.