Detention by non-state armed groups is a widespread, diverse, and legally complex occurrence in armed conflicts across the globe. In 2023, the ICRC assessed that around 70 non-state armed groups in non-international armed conflicts have detainees. The circumstances of detention can pose serious humanitarian concerns, including ill-treatment and inadequate living conditions for detainees.

In this post, part of a series on the Fourth Geneva Convention and the internment of protected persons and drawing upon the 2024 ICRC Challenges Report, ICRC Legal Adviser Tilman Rodenhäuser discusses the prohibition of arbitrary detention under international humanitarian law (IHL) and how this relates to internment by non-state armed groups in the context of non-international armed conflicts.