(note, I don't have alot of time, so I will make this quick)
In short, there was an Anti-Kazuth riot outside the guardhouse at Surna. It eventually got out of hand, swords were drawn, and several killed. It eventually led to (I'm guessing) a torch accidentally setting gunpowder off in the town, completely destroying it and alot of people in it. Outside the town, Occitianians waited for survivors, but many still escaped, and managed to make it to the town of Leyanara.
There you are, short 'n sweet. Someone may do a longer one later, but I don't have the time.
Also, you are given the choice of whether you want your character to die from this event, escape to Leyanara, to a different town, or whatever you like.