A medicament injection device comprising a main body arranged to receive a medicament cartridge; a needle carrier carrying a needle, wherein the needle carrier is axially movable with respect to the main body; and a rotatable cap at a distal end of the device, wherein the cap is removably coupled to the needle carrier, a releasable arrangement between the main body and the cap comprising a guide element and a slotted link, wherein the slotted link is arranged to cause the guide element to follow a predefined path at least partly in an axial direction during rotational movement of the cap, thereby causing the needle carrier to move axially towards a proximal end of the device as the cap is rotated up to a predefined point, wherein the main body comprises a medicament cartridge holder comprising the guide element depending therefrom for engagement with the cap.