I'm stuck at Lightning Bluff: Wong Manor. I have to kill all Wong's oci…

I'm stuck at Lightning Bluff: Wong Manor. I have to kill all Wong's ociates. So I did that and gathered my people as well but when I got to the very north all I see is a City Hall and a Sheriff. The task list has nothing on it so what am I supposed to do now? I've explored the whole place it's totally empty except for the Sheriff! Help please!