Pistol shrimp killing hermits?

[Waleedwale1]

So today I dropped a red leg hermit from one tank into my 29 biocube with a pistol shrimp and a YWG. The hermit landed upside down, in like 2 seconds my YWG picked him up and dropped him near the pistol shrimp who dragged him into his den. When I put my hand in the tank, he let the hermit go and he scurried away. I found another shell in the den. I think that the pair is well fed. Is this behavior normal?