The present disclosure relates to an auto-injector for delivering a liquid medicament, the auto-injector comprises an injector body, a syringe received in the injector body, a needle disposed in a first end of the syringe to extend toward an opening of the injector body, an injector cap to enclose the opening and cover the needle and a releasable attachment mechanism configured to secure the cap in place covering the needle. The releasable attachment mechanism comprises first and second engaging parts, wherein the first and second engaging parts cooperate in an attached position to secure the cap in position covering the needle, and wherein the attachment mechanism is configured to move into a release position in which the first and second engaging parts are in reduced cooperation when above a threshold temperature to facilitate detachment of the injector cap to expose the needle.
