A needle protector device comprising: a protector tube slidingly disposed in an outer tube and slidingly disposed over a syringe comprising a needle, said protector tube comprising at least one abutment initially in engagement with said outer tube such that said protector tube is constrained from moving distally with respect to said syringe, the outer tube comprising a proximal enlarged end in which a proximal hub of the syringe is received; a biasing device disposed inside said outer tube operative to provide an urging force on said protector tube in a direction that tends to urge said protector tube distally towards a tip of said needle; and a release mechanism operative to move said at least one abutment out of engagement with said outer tube upon distal pushing of a plunger of said syringe, such that when said at least one abutment is out of engagement with said outer tube, said biasing device urges said protector tube distally towards the tip of said needle; wherein said at least one abutment comprises at least one resilient tongue that tends to spring radially outwards from an outer contour of said protector tube, characterised in that, the release mechanism is disposed in outer tube and comprises a ring with proximally extending syringe interface members sitting in grooves of a shaft of the plunger and distally extending fingers each configured to initially not abut a respective tongue, wherein the release mechanism is configured such that upon distal pushing of the plunger, the head of the plunger contacts and distally pushes the syringe interface members which causes the distally extending fingers to push against an end of the respective at least one resilient tongue, thereby radially pushing the at least one resilient tongue inwards and out of engagement with the outer tube. a protector tube slidingly disposed in an outer tube and slidingly disposed over a syringe comprising a needle, said protector tube comprising at least one abutment initially in engagement with said outer tube such that said protector tube is constrained from moving distally with respect to said syringe, the outer tube comprising a proximal enlarged end in which a proximal hub of the syringe is received; a biasing device disposed inside said outer tube operative to provide an urging force on said protector tube in a direction that tends to urge said protector tube distally towards a tip of said needle; and a release mechanism operative to move said at least one abutment out of engagement with said outer tube upon distal pushing of a plunger of said syringe, such that when said at least one abutment is out of engagement with said outer tube, said biasing device urges said protector tube distally towards the tip of said needle; wherein said at least one abutment comprises at least one resilient tongue that tends to spring radially outwards from an outer contour of said protector tube, characterised in that, the release mechanism is disposed in outer tube and comprises a ring with proximally extending syringe interface members sitting in grooves of a shaft of the plunger and distally extending fingers each configured to initially not abut a respective tongue, wherein the release mechanism is configured such that upon distal pushing of the plunger, the head of the plunger contacts and distally pushes the syringe interface members which causes the distally extending fingers to push against an end of the respective at least one resilient tongue, thereby radially pushing the at least one resilient tongue inwards and out of engagement with the outer tube.