In both North and South, urban renewal and integration policies testify to the growing commodification of popular territories. The scientific literature emphasizes the processes of gentrification and population displacement associated with these dynamics, and questions the violent production of urban space primarily through the actions of the state and private developers. Shedding light on a blind spot in this discussion, this article proposes to study the forms of violence and commodification operating in the informal circuits of urban production and carried out by other actors, by studying an emerging figure in urban production in Latin America: illegal armed groups. In light of the recent capture of the informal land market by criminal organizations in Medellín, the article analyzes how land rights are distributed, legitimized or contested at the local level. We argue that the control of armed groups translates into the violent implementation of land predation that redefines forms of land valorization, access to land, and dwelling in popular neighborhoods, thus establishing predatory accumulation as the matrix of urban production.