I had a search through the forums to see if this has alreayd been posted and the most recent I was able to find was dated back in November 12th 2012.
The event is the one at the East End Tunnel location in the Brisban Wildlands asking players to destroy Fissures and then follow up to a Veteran Destroyer Crab. The current situation is 3/4 fissures have been destroyed with no location or sight of the fourth one within the event area.