Oh what little delights our fury friends are.
I saw my 2 pawing at a mouse in the garden, thankfully they did not bring it in too me.
My mums cat Tibby once brought one home, he had punctured the chest so the mouse was suffering. I remember my mum telling my to drown it so it didn't suffer. Not something i enjoyed doing but was definitely most humane.
It is such a shame they no longer catch them for food, only to play with.
Good luck with your parcel delivery service!