A little more information as I can consistently repeat this:
On the dam map move up the the second floor. Crouch and start going up the stairs to the third floor. Click on 135, 138, 1 and it is gone (going to the third level and clicking 135, 138, 2 will get him to the top).
Also I wasn't watching for it and can't remember if anyone looked into this yet, but I was able to move into the same squares as civilians while I was repeating it (although no crashes from that or anything).