What just happened?

We're back. All hell appears to have broken loose. Half the compound looks like it's been burned to the ground, there are zombies wandering around inside, the RV's and vehicles are gone and we have no idea where anybody is. We've secured an outbuilding now as a base and we're trying to clear the zombies out of the rest of the compound so that we can look for survivors or clues or something. This place is cursed.