Abstract: In a safety lock mechanism, including a locking bolt pivotable about a door hinge so as to be able to swing to a door-locking position and an electromagnet provided to retain said bolt in said door-locking position, apparatus arranged, so that upon the interruption of current supplied to said electromagnet and the application of a force on the door leaf to open the door, said bolt is urged to pivot to a door-releasing position, thus ensuring that the door is openable under all circumstances, even when considerable pressure is exerted thereon, such as e.g. from crowds of people in a panic.