Abstract: A security mechanism for securing a movable closure supported within a frame, the closure being movable from a secured position to a plurality of unsecured positions, preferably having a securing element having at least one opening, a base element, a slider element movably mounted on the base element and a latch element comprising at least one locking latch pivotally attached to the base element. The locking latch preferably has a first cam surface for engaging a cam post located on the slider element and a second cam surface for engaging the opening of the securing element. When the closure is moved to its secured position, the second cam surface of the locking latch engages the opening of the securing element thereby causing the locking latch to pivot and lock to the opening of the securing element.