The Special Intervention Detachment (French: Détachement Spécial d'Intervention, DSI, Arabic: المفرزة الخاصة للتدخل) is a police tactical unit of the Algerian Gendarmerie Nationale.
It was established to confront the increase in crimes and criminals, especially in its mode of action, as it offers adapted intervention possibilities and additional tactical capacities.
The training operations of different scenarios, always with live ammunition, are reviewed and debriefed to correct each action and try to improve its technicality.
DSI has trained a number of elite promotions from African countries in intervention and close protection.
The DSI has provided training in intervention and close protection to a number of elite promotions from African countries.