The present invention relates to a medicament injection device (100) that comprises a housing (110, 120) and an actuator (400, 500) configured for expelling medicament from a held reservoir (200) through an injection needle (250). A needle shield (150) is movable from a distal position through an intermediary position and further proximally to activate dose expelling. A carrier (300) movable within the housing (110, 120) holds the injection needle (250). A detent mechanism couples carrier (300) with the needle shield (150) as the needle shield (150) moves from the distal to the intermediary position. When the needle shield is moved further proximally the detent mechanism decouples the carrier (300) from the needle shield (150). A carrier spring device (680) is arranged between the housing (110, 120) and the carrier (300). The injection device (100) provides increased safety against potential damage to the injection needle (150) in case the injection device (100) is dropped on a hard surface.