I saw a news blurb on this yesterday, but it disappeared before I clicked on it.  When I read that they "had hidden bodies" (or whatever the headline was), I thought it meant that there were skeletal remains found within (or buried under them), rather than just that the statues themselves have sunk over the centuries.

I used the statues (with glowing red eyes!) in the V&V adventure "Devil's Domain" many years ago, and think of that every time I see something about them.