A pin located behind the slide lock and above the trigger on my Glock 35 Frame broke in half and fell out while I was firing the pistol. It looks like the part that broke and fell out of the frame was the Locking Block pin. I looked at an Exploded Drawing of a Glock at this website: http://membres.lycos.fr/shooter/glock/gdraw.html At the bottom left corner is the picture of a Locking Block pin in a Glock. This looks like the part that broke off. I do not believe that the pin which broke is the Trigger Pin (Part #28 on the Glock 17 Drawing). I have owned my Glock 35 for three years and put about 4500 rounds through it without any problems until now. My questions are: What might have caused the Locking Block pin to break? Is this a common occurrence in Glock 35s? Thank You in advance for any answer.