I learned this from a mod in food_porn
and spreading the word in communities I moderate. I'd suggest doing likewise. Apparently the same thing is happening in Facebook.
Something/someone is going around LJ and hacking accounts of users who mod large communities. After hacking the mod LJ, they go to the community, make a post with links, and then disable comments. They also delete all the community contents (as well as the contents of the mod LJs).
If you see a post claiming the community is going to be closed down with links to where the contents can be found... DO NOT CLICK. Check the screenshot below to see how genuine the post looks.
More info here: http://upstart-crow.livejournal.com/346623.html
<- This link is only a LJ post. The screencap below is what the suspicious entry would look like: