Two new cases of Early Chalcolithic arrowhead injuries are described. They come from the funerary site of Las Yurdinas II (Basque Country, Spain), a rock shelter with a little swallet where at least 90 subjects were interred. The lesions are located in a right humerus and a left ulna belonging to adult individuals, one of whom is a male, and both show signs of healing. Other possible signs of violence have been found in the collection, including one cranial trauma and two parry fractures. Both arrowhead injuries are set in the context of similar findings in the Middle Ebro Valley, assessing the number and distribution of cases, signs of healing, possible impact trajectory and the age and sex estimation of the individuals affected. Increasing social complexity and demographic pressure in the region may be causally linked to such an evidence. Copyright © 2015 John Wiley & Sons, Ltd.