Creature Feature - A Mysterious Burrow

As I was conducting my usual inspection of the plot last Sunday - I noticed something new and unusual.

There was a pile of newly dug earth at the side of one of my beds.

At first sight it looked like a rabbit or similar creature had been digging about. Or maybe I had a mole in residence ! ......

But - on closer inspection - I saw that something had dug itself a burrow.

Quite small - roughly mouse sized.

But  - I'm not sure that mice dig burrows like this.

Is it something else ? If you have any ideas please let me know - post a comment below.